A man was arrested overnight after driving a U-Haul box truck into a barrier near the White House, the US Secret Service said in a statement.
"There were no injuries to any Secret Service or White House personnel and the cause and manner of the crash remain under investigation," the statement said.
The truck crashed into the barriers at Lafayette Square, which is adjacent to the US president's residence.
Crash likely intended
US Secret Service spokesperson Anthony Guglielmi said the U-Haul was deemed safe, and that "preliminary investigation reveals the driver may have intentionally struck the security barriers."
He added that charges would be filed over the incident.
US media reports said that investigators found what appeared to be a Nazi swastika flag during the search, but no further information on the flag was provided.
According to the Washington Post, a nearby hotel was evacuated at the request of the Secret Service.
Officials said a call at 9:40 p.m. (0140 GMT) for a package investigation prompted a major law enforcement and public safety response. Investigators later reported that the U-Haul was mostly empty.