The building of Libya's External Security agency in Tripoli was bombed early Friday in an apparent NATO airstrike.

A Xinhua reporter went to the bombed target in a eastern district of the Libyan capital after hearing four loud explosions.

He saw a building of the External Security agency was on fire as fire trucks and ambulances were rushing to the scene in the eastern Tajoura district.

Casualties from the latest bombing were not immediately known.

The building was bombed by NATO warplanes a month ago.