A booby-trapped car exploded on Thursday morning in front of a police station in Zawyet el Dahmani area in Tripoli.
"No casualties were reported," said a security source.
He added that a number of parked cars near the police station were damaged by the explosion.
Tripoli residents had heard the sound of a strong explosion in the wee hours of Thursday.
Tripoli has been in turmoil since the removal of Libyan president Muammar Gaddafi from power in 2011.