The White House was briefly on lock down Friday afternoon after a shooting outside the perimeter that involved a uniformed Secret Service officer, a D.C. Metropolitan Police Department spokeswoman said.

The Secret Service reported that an adult male approached an outside perimeter checkpoint on E Street carrying a gun. When he refused officers’ repeated commands to drop the gun, a Secret Service agent shot him once, according to the statement.

The gunman was taken to a local area hospital for medical treatment for what D.C. Fire and Emergency Services described as “critical” injuries.

UPDATE: Shooting at 17th and E Sts NW – 1pt transported with critical injuries to a local hospital #dctraffic

— DC Fire and EMS (@dcfireems) May 20, 2016

President Barack Obama was not at the White House at the time of the shooting — he was at Joint Base Andrews for a Friday afternoon round of golf before departing Saturday for a week-long trip to Asia.

Witnesses described a chaotic scene as Secret Service agents moved quickly to secure the area.

Akil Patterson of Baltimore said he was visiting the White House on Friday with a group of about 60 men who were to be honored for their community service in urban communities.   

Patterson told a group of reporters he was in the second security line when he heard a gun go off.   

“All I heard was one shot fired – boom. Backfire,” Patterson said. “It sounded like a muzzle sound.”  

About 30 seconds later, Patterson said, he heard a Secret Service radio go off: “Suspect down. Suspect down. Shot fired. Shot fired.”  

Patterson said despite not being outside the White House, he expected to shelter in place. Instead police asked about 100 people on the security line o go outside near F Street where he described the scene as “mass confusion.” He said he was not able to cross 17th Street for some time because so many police cruisers were racing down the road attempting to block traffic. 

Eddie Connor, who did a stint on the Hill as an aide to former Michigan congressman Hansen Clarke was in town from Detroit to receive a White House leadership award.   

He said he heard one shot while waiting in a security line at the Eisenhower Executive Office Building (EEOB) near 17th and E streets NW.  

“It was a little slight hysteria,” Connor said. “The Secret Service were arming themselves. … They were yelling, saying, ‘Move, move! Immediately!’”  

[
Paul Touts DC Gun Bill as Shooting Near White House Unfolds
] A Secret Service officers inside a small building at a security checkpoint outside the EEOB known colloquially in Washington as the “appointment gate” appeared to hear the shot. Several witnesses said he immediately glanced at another officer inside and asked, “What was that?”  

One was Nana Malaya Rucker of D.C., who was waiting to see her son receive the same award.  

“They had my I.D. card. I was standing there, getting ready to go through,” Rucker said. “One of the officers jumped out of a car and said, ‘Everybody’s got to go back. Shots fired.’ That’s all I heard. We turned around and started moving quickly.”  

Rucker said she did not immediately know it was a gunshot, while another witness said he knew instantly.  

“Oh yeah,” he said with a knowing nod. “I knew. If you’ve ever heard gunshots, you knew.”  

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