Angry crowds have attacked diplomatic buildings in the Libyan capital Tripoli following reports that one of Col. Gaddafi's sons was killed in a NATO air strike. The British embassy was completely burnt out. Libya's deputy Foreign Minister said police had been out-numbered and he promised that the damage would be repaired. After its Tripoli embassy was sacked, the UK expelled the Libyan ambassador. The UN has withdrawn all its international staff from the Libyan capital Tripoli following a mob attack on its offices. The UN says all its international staff have now left for Tunisia and the decision will be reviewed next week. In other developments, witnesses reported heavy shelling by pro-Gaddafi forces on the port of Misrata on Sunday. Libyan state TV said the port was shelled to stop Nato delivering weapons to insurgents but rebels said an aid ship had been trying to unload.