A car that trailed a motorcade carrying President Barack Obama's daughters prompted a security lockdown at the White House.
A spokesman for the US Secret Service said the car entered the security checkpoint at 17th Street and Pennsylvania Avenue near the White House and was immediately stopped by Secret Service officers.
The male driver was arrested and Washington police then checked the car for explosives.
People were unable to leave the White House grounds while the car was being searched - the security lockdown was lifted after more than an hour.
The motorcade was carrying Obama's daughters, Sasha and Malia, a source told Reuters.