Libyan leader Colonel Muammar Gaddafi is said to be arming volunteers to fight the uprising against his rule, a senior US military official has said.
Vice Admiral William Gortney said Col Gaddafi had “virtually no air defence” and a “diminishing ability to command and sustain his forces on the ground”.
Coalition forces launched strikes against Libyan tanks around the eastern town of Ajdabiya, he said.
Rebels and pro-Gaddafi forces are in a stand-off near the town, witnesses say.
Meanwhile, Qatar became the first Arab state to contribute to the air mission over Libya.