Muammar Qaddafi spoke to the local Tripoli radio station Tuesday that was then broadcast over Al-Orouba TV, broadcasting in conjunction with Al-Rai TV. Qaddafi refused to give up fighting in the speech, Reuters reports. He described his decision to leave his Bab al-Aziziya compound as a "tactical move." Rebels broke into the compound Tuesday afternoon, where it was suspected Qaddafi was hiding, but he was nowhere to be found. Qaddafi remained defiant in the face of defeat when he promised "martyrdom or victory" in his fight against NATO and the rebels, according to Reuters. He also claimed most of the compound was destroyed as a result of 64 NATO air strikes. BBC News explains how he might have escaped from the house before rebels could get to him: 

It is not known if Col Gaddafi and his family were in Bab al-Aziziya on Tuesday, but the complex is reported to be connected by underground tunnels to various key locations across the city.

The Gaddafi family are also believed to have access to numerous safe houses in Tripoli and beyond.

Al-Jazeera English's Andrew Sullivan reports the escape tunnels could even be big enough to accomodate vehicles, and some tunnels are "up to 30 kilometres long, according to some reports." Sullivan reports on a number of updates from the ground in Libya in the video below. 

Update: Reuters have new quotes from Qaddafi's remarks in the radio interview. He said residents in Tripoli must "cleanse" the city of rebels, as well as these remarks: 

"All Libyans must be present in Tripoli, young men, tribal men and women must sweep through Tripoli and comb it for traitors," the Libyan leader said. "I have been out a bit in Tripoli discreetly, without being seen by people, and ... I did not feel that Tripoli was in danger," he added.