At around 18:00 local time (23:00 GMT), a volley of gunfire was heard by multiple journalists who were present at the White House.

Members of the Secret Service ushered them inside the building to the press briefing room, and the White House was placed under lockdown.

Sources told CBS News, the BBC's US partner, that between 15 and 30 gunshots were fired, and that it appeared to be a single gunman who had approached Secret Service agents and shot at them unsuccessfully. Those agents then returned fire.

US media has since reported that two people were wounded in the shooting, and both have been taken to hospital. CBS reports that one of those people is the suspect, who they say is in critical condition, and the other is a possible bystander.

The lockdown at the White House was then lifted at 19:00 local time (00:00 GMT).

We have not yet heard anything from President Donald Trump, who was in residence at the White House at the time of the shooting. It comes just one month after a gunman opened fire at the White House Correspondents Dinner.