(Brendan Smialowski/AFP/Getty Images)

The White House went on lockdown this afternoon around 4:40 p.m. after a car somehow made it past the barricades on Pennsylvania Avenue, authorities said.

Security officials closed the gates, cleared the North Lawn, and asked occupants to stay inside the building after a blue Honda Civic crossed a checkpoint and parked near the White House's front entrance.

The driver of the car was a "Treasury Department pass holder" who was not authorized to cross the secure perimeter, secret service said.

The driver, who appeared to be trailing a motorcade transporting the first daughters, was immediately stopped by Uniformed Division officers and is now in custody.

As Secret Service ushered pedestrians off the sidewalks and cordoned off nearby Lafayette Square, ambulances and fire trucks arrived on the scene.

MPD also conducted a sweep of the vehicle.

Secret Service agents mill about a car that drove up to the White House pic.twitter.com/dl5Qk1YCew

— Chris Good (@c_good) May 6, 2014

The Secret Service re-opened the North Lawn and the northwest gate at about 5:40 p.m., though parts of Pennsylvania Avenue remained closed.

ABC News' Ann Compton, Mary Bruce, Chris Good, Jack Cloherty, and George David Sanchez contributed to this report.