A uniformed U.S. Secret Service agent mistakenly fired his weapon while he was on duty near the Russian Consulate office in Northwest Washington early Wednesday morning, according to Secret Service officials.

Nobody was injured in the incident, authorities said.

The officer was sitting in his marked cruiser in the 2600 block of Tunlaw Road when his gun went off once at 3:50 a.m., said Jim Mackin, a Secret Service spokesman. The consulate is located next to the Russian Embassy.

The officer was part of the Foreign Mission Branch of the Secret Service, which provides security to foreign governemts on U.S. soil. His car was damaged by the bullet, Mackin said.

The Secret Service has opened an internal investigation into the matter. Mackin would not say whether the officer was assigned to the Russian Consulate when his gun discharged.