Security threat interrupts White House press briefing from Medill Washington on Vimeo.

The evacuation came in the middle of a televised press briefing by Press Secretary Josh Earnest. The North Lawn of the White House was also cleared.

PHOTOS, STORIFY: Bomb threat sparks evacuation of White House press briefing 

Secret Service officials said the threat was called in at 1:53 p.m. About 30 minutes after the call journalists were allowed back into the White House. Secret Service officers on the scene said an all-clear had been issued.

“As a precaution, the White House Briefing Room was evacuated,” Secret Service spokeswoman Nicole B. Mainor said in a statement. “The evacuation was limited to the White House Press Briefing Room and did not affect any other sections of the White House.”

Shortly after the evacuation Earnest wrote on Twitter that the briefing would resume shortly after the room was cleared. “Hopefully won’t be long,” he wrote.

“At approximately 1:53 p.m. today, a telephonic bomb threat concerning the White House Briefing Room was called into the Metropolitan Police Department,” a Secret Service statement said. “As a precaution, the White House Press Briefing Room was evacuated.”

According to the statement, no other parts of the White House were affected by the evacuation.

“Sweeps concluded at 2:36, the area was declared safe, all occupants were returned to the White House Press Briefing Room,” the statement continued.

You can view photos from the scene below:

Here is a moment-by-moment rundown of the evacuation, as narrated by reporters who were attending the briefing when the evacuation occurred via social media:

TWENTYNINE PALMS, Calif. – Getting stationed in California should sell itself: Sun, sand and mountains. But that’s not the case for some Marines assigned to Twentynine Palms Marine Air Ground Task Force Training Command and Combat Center — an hour northwest of Palm Springs in Southern California.

The base is centrally located between the mountains, ocean, Las Vegas, San Diego and Los Angeles, but all are several hours away. The nearby town of Twentynine Palms – population 26,000 — offers few entertainment options, especially for young Marines without a car.

Some Marines describe Twentynine Palms as a “difficult duty” station because of the limited free-time activities. Others see the isolation as a tradeoff to get the exceptional training offered at the base.

“I did not pick it, but you know you’ll be the best if you go here,” said Pfc. Ryan May, who works with heavy artillery. “So, you can’t really be mad about it.”

May and others said the opportunities to hone their training are almost as boundless at Twentynine Palms as the base itself. It is slightly bigger than Rhode Island, offering Marines the chance to do live fire exercises daily.

“That’s what the Marines like to do: Make things go boom,” said Mike King, a former Marine who served 15 of his 20 years at Twentynine Palms. “You can’t do the things we do here on this base anywhere else so it’s practical application of what they’ve been trained to do.”

The U.S. government created Twentynine Palms in 1949 because more live-fire ranges were needed for training. Many Marines not stationed there often cycle through it for training. The Integrated Training Exercise is a month long program focusing on warfare maneuvers for global operations. Currently, the base is used for pre-deployment training for missions in the Middle East. The desert terrain at Twentynine Palms mimics conditions troops will face in places like Iraq and Afghanistan. Exercises also are conducted in a mock Middle Eastern village on the base.

The size of the base allows Marines to do more than just shoot large guns. The desert space also gives tank units room to practice moving their machines, which can be limited on other bases. Fewer space restrictions give the Marines more opportunity to see how the tanks perform, move and break down.

Tank mechanic Staff Sgt. Adam McPherson chose to be stationed at Twentynine Palms because of the hands-on experience it would provide.

“The tanks get used a lot,” he said. “We go to the field quite often out there and mechanics get that first-hand experience fixing them.”

McPherson believes because there are so many field exercises at the base he has more knowledge about his vehicle than a Marine who has not been stationed at Twentynine Palms.

The base also features the largest urban warfare training center, Range 220, in the Department of Defense, not just the Marine Corps, according to King.

“When you’re talking Range 220 here in Twentynine Palms, 1,500 buildings compose the size of about downtown San Diego. There’s no other place on the planet you can get this type of training.”

But after the training ends, the boredom begins – at least for some Marines. Most are males between the ages of 19 and 24, according to King. About 7,000 of the 10,500 Marines are single, said Capt. Justin Smith, the base’s public affairs officer. Drive around the city of Twentynine Palms and you will find many tattoo parlors and barbers, but you will not see any of the strip parlors that cater to many other military bases.

“Twentynine Palms, the city itself, is more family-oriented,” said King.

With limited entertainment options round the base, boredom can drive Marines to extremes. There is a saying at Twentynine Palms: Marines either become drinkers, gym rats or find religion.

Capt. Jonathan Zarling admitted single Marines can struggle with their social lives.

“You’ve got to travel to it,” he said. “Single guys on the weekend are usually wondering, ‘What do I do?’”

“We have each other out here to hang out with,” said Cpl. Jacob Evans. “We’ll just hang out at each other’s houses and grill, have a few drinks.”

For some, the desert has advantages for entertainment.

“I actually enjoy it because I’m a dirt bike rider,” said Sgt. Ricky Bajo. “There are a lot of dirt places here.”

Bajo has spent six years at Twentynine Palms and rides his dirt bike almost every weekend. Other Marines said they found the seclusion of the desert and base comforting.

“I like it here because I come from a small town where I was already isolated,” said McPhearson, who also has spent six years on the base. “The quiet is nice. I don’t like the hustle and bustle of the city, so for me it’s OK.”

The base offers discount entertainment options. There is a movie theater where Marines can see first run movies, restaurants, a fitness center, clubs, concerts, sporting events, stories, classes and seminars. Different commands throughout the Marine Corps also host various functions depending on the amount of recreational funds they receive, including day trips to popular destinations said Smith.

King advises young Marines to save money to buy a reliable car so they can take advantage of the ocean, mountains and big cities all a few hours’ drive from the base.

“If you cannot find something to do, you’re not trying hard enough,” he said.

Rep. Federica Wilson, (D) – Florida, is giving a speech Wednesday at the Capitol to remind people of the Nigerian schoolgirls who were kidnapped by Boko Haram one year ago. (Andersen Xia/MEDILL)

WASHINGTON — Marking the one-year anniversary of the abduction of 276 Nigerian schoolgirls by Boko Haram, lawmakers spoke at the Capitol Wednesday. Two girls who escaped, along with some 50 others, attended the press conference. The House Foreign Affairs committee is considering funding to resettle some of the displaced people in the U.S., using some of millions of dollars seized by the United States from former Nigerian dictator Sani Abacha. The new Nigerian President Muhammadu Buhari said Tuesday in a statement that he cannot promise to find the remaining missing girls.

WASHINGTON – Two prominent National War College professors of Strategy and Policy gave reporters a detailed look at how Islamic State terrorist group recruits and operates during an April 6 National Press Club panel.

The event, cosponsored by the Medill National Security Journalism Initiative (NSJI) and the National War College, and moderated by NSJI Director of Education and Outreach Josh Meyer, sought to increase the media’s knowledge of the Islamic State.

The analysis by Dr. Omer Taspinar and Dr. Richard B. Andres broke down into two sections: the relationship between radicalization and the Islamic State’s rise to power, and the role of social media in radicalization.

Radicalization and the Islamic State

Taspinar said that the creation of the Islamic State is, at its core, a result of Sunni Muslims’ oppression by a Shiite majority within Iraq.

According to Taspinar, de-Baathification in Iraq – or the breakup of the Saddam Hussein-led Baath Party – led to the rise of a Shiite majority within the country, a backlash against Sunni Muslims and the birthing “a sense of Sunni resentment.”

“It’s very hard for the Sunni minority of Iraq to come to terms with the fact that Shiites now are running the country,” he said, noting that Sunnis had historically possessed control of the country from its initial founding until the Baathist fall.

Taspinar also teaches at the Johns Hopkins School of Advanced International Studies and serves as a Nonresident Senior Fellow at the Brookings Institution focusing on foreign policy and working with the organization’s Center on the United States and Europe.

He went onto explain that former Baathist leaders became delegated to a lower class and “felt persecuted.” The resulting anger, he said, fueled radicalization. According to Taspinar, in the wake of the Shiite rise to power, Sunnis suffered from collapses in security, capacity and legitimacy (or the descrecration of their former socioeconomic and political status).

“All this contributed to the rise of ISIS, which captured basically the most radical elements within the Sunni groups … starting in Syria,” he said.

Iraqis who sympathized with the radical parties in Syria started crossing the border to join ISIS, he continued.

“ISIS did something that no other radical Salafist jihadist organization managed to do: It established a state — it declared a state,” Taspinar said.

The idea of a caliphate with sovereign government and territory that came with the promise of a return to prophet-era morals and living (and in which Sunnis could return to a once-held state of glory) appealed to disenfranchised Sunnis and drove recruitment, he said.

“You have to understand that, for people in the Islamic world, especially the disenfranchised radicalized youth, there’s this strong sense of nostalgia for the golden age of Islam – the days when Islam was able to actually create a great civilization which surpassed the West in terms of its scientific, architectural, artistic, military achievements,” he said.

The idea of citizenship in such a state – as opposed to membership in a terrorist group like al-Qaeda had long promised – appealed to Muslims in Europe, North Africa and the Middle East.

Joining ISIS’ “Islamic utopia” was made even easier by geography, Taspinar explained, since all one had to do was cross the Syrian border to arrive.

Taspinar attributes the recent spark in the Islamic State’s recruitment of middle-class, educated individuals from Europe to “relative deprivation.”

He explained this concept as the process by youth become disheartened with the lack of employment avenues despite their education and a “sense of perceived racism” that makes them believe their upward socioeconomic mobility is limited by their Muslim identity. According to Taspinar, the dismal outlook breeds “frustrated achievers.”

In this sense, he explained, there’s more to the Islamic State recruitment than just religious ideology.

According to Taspinar, its early days, the Islamic State was largely unconcerned with the West, more focused on preserving the integrity of its self-declared state in terms of governmental and territorial control.

However, according to Taspinar, its dedication to maintaining caliphatic sovereignty meant that it felt compelled to respond to threats made upon it by outside forces – such as the United States government. This, in turn, sparked the group’s evolution into a more violent form that we, as Westerners, are more familiar with seeing stream across our TVs and occupy our headlines.

How Social Media Radicalizes

Richard B. Andres, who has 16 years of teaching experience and serves as the Energy and Environment Security Policy Chair at the Institute for National Strategic Studies, took a different approach to radicalization.

Rather than examining it in the context of geopolitics, he tackled it in the key of cyber, contextualizing the roots of social media’s capacity to radicalize its users and how that capacity has been used by the Islamic State.

“There’s two particular psychological things politically that social media takes advantage of,” Andres explained.

The first is that, since “human beings are attracted by sensation,” we are literally wired to fall for clickbait. The second is that people are psychologically more likely to click on things that backup our preexisting opinions.

“That’s why Republicans watch Fox News and Democrats watch MSNBC,” Andres explained.

According to Andres, social algorithms serve up social content that plays to preexisting biases, beginning with more mainstream, subtle pieces and eventually building up to obviously radical ones. That helps push people, especially young and impressionable males – toward radicalization, he said.

“Social media will inadvertently… push you more and more like a cult to the point where you’re isolating [sic] from friends, you’re isolating from ideas, all the way to the extreme,” he said.

However, he says traditional media is necessary to fuel the fire, since it supplies content to feed the effect. Content distributed through social channels needs to come from somewhere (since Facebook and Twitter aren’t news organizations), so, like it or not, the inherent biases present in news coverage contribute to the cult effect.

Levels of susceptibility differ, he said, but people who come from “autocratic” countries whose governments keep citizens distanced “from non-biased information” are more likely to fall for the effect, which Andres called “clickwashing.” He says that is because their experience with strongly biased media makes more moderate mainstream coverage seem less trustworthy.

But social media’s radicalizing tendencies don’t stop at creating lone wolves. In fact, Andres noted, its other radicalizing strength does quite the opposite.

“Social media allows people to coordinate their behavior,” he said. “The main defense that autocracies have against dissidents and rebels is they prevent people from coordinating.”

Andres said that the uniting nature of social media helps to counteract suspicions of surveillance that radicals might have, helps you find people who will – much like the aforementioned content – reinforce your extreme biases, and plan tangible gatherings.

ISIS has capitalized on these characteristics of social media to “groom” potential terrorists via clickbait, he said.

It accomplishes this in a five-step manner, Andres explained.

First, he said, ISIS makes “sensationalist images” of graphic violence and other click-inducing things. He noted that Islamic State social followers generally don’t stay engaged by this kind of content, but that it is effective in making first cyber contact via clicks.

Next, he said, they designed those images to link to actual news stories about ISIS’ impact around the world in order to make themselves appear more legitimate.

Third, he said, they “flood Twitter” with identical, radicalizing stories to the point where potential recruits have no choice but to be pulled in due to the psychological pull discussed earlier.

Fourth, he said, they reach out to potential recruits in covert ways, such as through the use of onion routing (such as Tor) to mentor them and to arrange fund transfers associated with joining up.

Finally, he explained, they use social as a way to arrange travel to an ISIS location.

From there, Andres said, the Islamic State uses “the wisdom of the Marine Corps” to pull people with privilege in.

“What the Marine Corps does, it says: ‘This is a cause that’s worth dying for; come fight with us. You’re gonna live in the mud, we’re gonna kick your butt and call you names. It’s gonna be really, really hard, but you’re gonna do something important. You’re gonna suffer and you’re gonna fight.’”

“That message resonates with young people very strongly,” he explained.

According to Andres, this is evidence that the Islamic State has figured out a key factor in the human psyche: People are also wired to want to make a difference in the world – “not just to live well.”