Two people have been injured in an accident involving a State Department motorcade outside the White House.

The incident happened at 12.55pm when a protester jumped in front of the vehicle and was brought down by a Secret Service officer.

The Chinese Vice Premier Liu He was among those being transported in the motorcade along with other delegates who had been invited to the White House to discuss trade.

It is not clear if the protester knew whose motorcade they were targeting or what they were there to grandstand about.

A protester leaped in front of an official government motorcade on Wednesday at 2.15p and was brought down by a Secret Service agent. Shown above is the scene afterwards

Police blocked off 17th St NW near F street, where the incident took place, afterwards

Chinese Vice Premier Liu He (center) is shown at the White House on Wednesday morning before the incident. He was inside one of the cars when the protester leaped in front of it

The president was in the White House all day. His only scheduled event was an intelligence briefing.

Vice President Mike Pence was also in the White House on Wednesday afternoon to greet a recently released prisoner who was freed under Trump's prison reform.

The Secret Service would not confirm who was in the motorcade at the time of the incident.

In a statement, a spokesman would only give brief details of what occurred.

'On Wednesday, January 30, 2019, at approximately 12:55 pm, near 17th and F Streets NW, U.S. Secret Service Uniformed Division Officers arrested one individual for Crossing a Police Line and Assault on a Police Officer after they attempted to impeded the progress of vehicular traffic in a temporarily secured area.

'The individual will be transported to MPD 2D for processing,' a spokesman said in a statement. The protester has not yet been named.

The Secret Service blocked off sections of the road on Wednesday after the protester was arrested. A Secret Service agent was also injured but not seriously