The White House went into lockdown briefly Tuesday after a Treasury Department employee followed a motorcade carrying Sasha and Malia Obama onto Pennsylvania Avenue.

A Secret Service spokesman said the lockdown lasted roughly an hour and confirmed that that the driver of the unauthorized vehicle was a holder of a "hard" access pass from Treasury. Authorities later identified the driver as 55-year-old Mathew E. Goldstein and charged him with unlawful entry.

Goldstein was still in custody as of Tuesday evening, and it was not immediately clear whether his actions were intentional.

The Secret Service lifted the lockdown after searching the vehicle on Pennsylvania Avenue.

This article was originally posted at 6:20 p.m. and has since been updated.