The anti-aircraft gunfire began at around 0430 GMT and there were ensuing blasts, the journalist said.
The official JANA news agency said coalition raids in Tripoli on Wednesday had killed "a large number" of civilians, including rescuers trying to remove the dead and wounded from rubble.
Witnesses on Wednesday reported a huge blast at a military base in the Tajura residential neighbourhood 32 kilometres (20 miles) east of the capital, while anti-aircraft fire was heard as warplanes thundered over Tripoli.