The White House was reportedly placed under temporary lockdown after a car rammed a security signpost at Lafayette Square. Secret Service has arrested two people after the car breached a barricade and crashed outside the White House, reported Fox News.

Several videos on the internet show smoke emerging from the bonnet of a car as security officials rush to contain the situation. As Secret Service officers responded to the crash, they instructed media personeel present at the White House to go inside the premises, according to local reports.

Sniffer dogs were reportedly brought in to look for explosives after the crash.

"Just before 10:00 a.m., Secret Service Police and National Guard responded to the north side of Lafayette Park at 16th Street and H Street, NW, where a vehicle crashed onto the sidewalk. The driver was combative with law enforcement, but was quickly placed under arrest," Fox News quoted a Secret Service spokesperson as saying.

The spokesperson added that a second person jumped a barricade near the northwest corner of Lafayette Park and was immediately placed under arrest.

"MPD's Explosive Ordinance Disposal team has been called to sweep the vehicle as a precaution. Subsequently, roads around Lafayette Park have been closed," the statement said.

Further details are awaited.