The accused gunman who tried to storm the ballroom at the White House Correspondents’ Association dinner travelled across the country before the yearly event and is believed to have been targeting members of the Trump administration, acting Attorney General Todd Blanche said Sunday. Mr Blanche also said officials believe the suspect headed by train from California to Chicago and then on to Washington, where he is understood to have checked in as a guest to the hotel where one of Washington’s glitziest events was being held Saturday night.

The suspect, said to have been carrying weapons, has been identified as Cole Tomas Allen, 31, of Torrance, California. One officer who was shot but protected by his bulletproof vest was taken to hospital. He faces charges including assaulting an officer with a dangerous weapon, but Mr Blanche said additional charges will be filed.

Law enforcement officials who have examined the suspect's electronic devices and his writings preliminarily believe the suspect intended to target administration members in attendance at the dinner.

The suspect allegedly attempted to charge into the cavernous ballroom but was tackled to the ground in a chaotic scene that resulted in shots being fired, President Donald Trump being rushed off the stage and guests ducking for cover beneath their tables.

The suspect is believed to have purchased the firearms he carried within the last couple of years, Mr Blanche said.

“It does appear that he did in fact set out to target folks who work in the administration, likely including the president,” Mr Blanche told NBC’s “Meet the Press.”