State television in Libya has broadcast what it says is an audio message from Colonel Muammar Gaddafi saying he will remain in the country "dead or alive".
The message came a short time after NATO carried out one of its heaviest daytime raids on Tripoli so far with more than 20 air strikes by low-flying jets, the BBC reports.
Some of the bombs hit a military barracks near the compound, officials said. Others hit the compound itself, Libyan television reported.
Until now, most Nato air strikes in Tripoli had been carried out at night. The alliance recently said it was increasing the scope and intensity of its UN-mandated campaign to protect civilians.
In his message, the Libyan leader called on his supporters to defy NATO air strikes and gather in his compound in Tripoli.
Colonel Gaddafi said martyrdom would be a million times better than surrender.