At least five blasts rocked the Libyan capital after NATO planes flew over Tripoli.
According to rebel reports, mortar shells and rockets also rained on the coastal city of Misurata.
Three blasts could be heard from the city centre at around 11:00 pm (local time) on Thursday, followed by two others a few minutes later.
Witnesses said they saw smoke rising from the Ain Zara district in the southeast, which has been regularly targeted by NATO war planes.