Image source, AFP via Getty Images

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.

Images from the streets surrounding the White House show dozens of police officers and other law enforcement officials.

Image source, AFP via Getty Images

Image source, AFP via Getty Images

Image source, AFP via Getty Images

More now from law enforcement sources who have been speaking to our US partner CBS News.

Sources say it appears a person shot at Secret Service agents unsuccessfully, and the agents returned fire.

Several Secret Service agents were evaluated at the scene, but none of them were deemed to need hospital treatment.

Between 15 to 30 gunshots were fired during the incident, the sources say.

Two people have been wounded in the shooting near the White House, law enforcement sources tell the BBC's US partner CBS News.

The two people - a suspect and a possible bystander - have been taken to a local hospital, the sources say.

The suspect is said to be in a critical condition and the other individual in a serious condition.

Multiple journalists at the White House reported hearing a volley of around 20 gunshots, before they were ushered into the famous press briefing room inside the building.

Photos taken inside the building show journalists crowded by the windows:

Image source, Getty Images

Emer McCarthy
Reporting from Washington DC

Image source, AFP via Getty Images

I’m at the corner of H and 17th Street, just a few blocks from the White House where police have just taped off the road.

There are several police cars and media gathered, as well as onlookers.

Several journalists have posted on social media about being near the White House for other work when they heard gunshots.

In one video, external, Selina Wang, a reporter with ABC News can be seen ducking for cover when she hears gunshots while recording a video for social media.

"It sounded like dozens of gunshots," she says. "We were told to sprint to the press briefing room where we are holding now."

These images have just come in showing armed police near the White House:

Image source, Getty Images

Image source, Getty Images

We've just had a statement from the Secret Service spokesperson Anthony Guglielmi.

In a statement to CBS News, the BBC's US partner, he says the agency is aware of "reports of shots fired near 17th Street and Pennsylvania Avenue NW" and are "working to corroborate the information with personnel on the ground".

FBI director Kash Patel says the Secret Service is responding to shots fired near the White House.

We'll bring you more on this shortly.