The strikes were almost continuous for about a half-hour, The New York Times reported. The center of Tripoli was blanketed with smoke and fireballs.
"We thought it was the day of judgment," one angry witness told the Times.
Moussa Ibrahim, the chief government spokesman, said the bombing had killed three civilians and injured about 150. He said most of the strikes hit a Popular Guard compound that had been evacuated because it was believed to be a target.
NATO officials released a statement saying the bombs were dropped on a "vehicle storage facility" next to Gadhafi's command compound.
The raid was the heaviest on Tripoli so far and suggested NATO is trying to break what has become a stalemate in Libya. There were other signs of such a development Monday, including a visit by Jeffrey Feltman, the senior Middle East official in the U.S. State Department, to the de facto rebel capital of Benghazi.
French Defense Minister Gerard Longuet announced Britain and France plan to add helicopter gunships to their forces involved in the Libyan air war.