US Secret Service shoots armed man outside White House

The US Secret Service has shot an armed man who had brandished a gun outside the White House, according to US officials.

Police told ABC News that a man had brandished a gun at a security checkpoint near the White House on Friday and was shot in the stomach. He was transported to hospital with critical injuries.

"Secret Service Uniformed Division Officers gave numerous verbal commands for the subject to stop and drop the firearm," security agencies said in a joint statement.

"When the subject failed to comply with the verbal commands, he was shot once by a Secret Service agent and taken into custody. At this time, based on a preliminary investigation, there is no known nexus to terrorism."

The White House was briefly placed on lockdown after the shooting. President Barack Obama was playing golf in Maryland at the time. Vice-President Joe Biden was in the White House at the time, and White House officials say he was taken to a "secure area" during the incident.

The White House has seen a number of security incidents in recent years, prompting changes at the executive complex.

In April, the Secret Service caught an intruder climbing over the White House fence.

In 2014, Iraq War veteran Omar Gonzalez jumped the White House fence and ran into the building with a knife. Also that same year, a toddler squeezed through the gates of the fence and was caught on the lawn.

In 2013, a man tried to crash a jeep filled with knives and bullets into a security gate.

In 2011, Oscar Ortega-Hernandez shot at the White House and was charged with attempting to assassinate Obama or a member of his staff. Ortega-Hernandez reportedly believed God had given him a personal mission to attack the White House.