Gaddafi`s son Saif al-Islam needs surgery on gangrenous fingers.

Muammar Gaddafi's son Saif al-Islam needs surgery to remove gangrenous flesh from a severed thumb and finger which if not treated could make him seriously ill, a doctor who examined him told Reuters on Thursday.

Saif al-Islam has been nursing injuries to his right hand which he says were sustained during a NATO airstrike weeks ago. No further details have been available on the state of his heavily bandaged thumb, index and middle fingers.

"This wound is not in good condition and requires amputation," Andrei Murakhovsky, a Ukraine-born doctor working in Zintan, the town where Saif al-Islam is being held, and who treated him three days ago told Reuters. "The wound is covered with gangrenous tissue and necrotic tissue," Murakhovsky added.

Fighters from Libya's Western Mountains captured Saif al-Islam in the southern desert on Saturday and flew him to their stronghold town of Zintan, where he is being held pending a handover to the country's provisional government.

Saif al-Islam's middle finger did not require surgery but the two other bandaged digits had been severed and were weeping pus, said Murakhovsky, who was interviewed by Reuters television in English and later by telephone in Russian.

"His index finger has been ripped off at the level of the middle phalange (finger bone), the bones are all shattered, It's the same thing with the thumb of that hand," he said.

When a picture of Saif al-Islam's bandaged hand was aired, many Libyans thought his captors had cut off his fingers in retribution for televised remarks in which he threatened anti-Gaddafi rebels, pointing and making other hand gestures.

Murakhovsky, however, said the injuries were consistent with "some kind of explosion."