Libyan leader Muammar Gaddafi's son Khamis was killed in a NATO airstrike in the west town of Zlitan, which also led to the death of some 30 others, a rebel spokesman said.

Khamis commanded Libya's 32nd Brigade, one of the most reliable Gaddafi forces, which has been deployed in Zlitan, the biggest urban area between Misrata and the capital Tripoli.

The Libyan government and NATO have not confirmed the death so far.