Nato has acknowledged its air strikes in "may have" resulted in the deaths of rebel forces on the ground in Libya yesterday - but will not apologise.
The military alliance did not know the rebels were using tanks, spokesman Rear Admiral Russell Harding said after the attack, which killed at least five people.
But a rebel commander earlier claimed Nato had been told the rebels were moving T55 and T72 heavy tanks from Benghazi to Brega.
General Abdul Fatah Younis said at a news conference in Benghazi that fighters and medics were among the dead after the bombing "carried out in error".
Saleh Faraj, a former soldier fighting with the rebels, said at least three rebel tanks were hit in the air strike.
"There was no fighting anywhere. (The warplanes) flew back and forth and then they struck our forces," said Faraj.
The incident came ater the rebels criticised Nato for failing to provide the assistance it requires.