BRITISH forensic experts investigating the assassination of Pakistan opposition leader Benazir Bhutto are unlikely to discover who killed her, her supporters said after her son and political heir Bilawal Zardari appealed for a UN probe into the murder.

'We will cooperate with the team from Scotland Yard, but we don't think it will reveal the true facts,' said Farhatullah Babar, a spokesman for Ms Bhutto's political party, adding that only an independent investigation would be able to unmask who orchestrated the attack.

Officers from the British team have so far examined the car that Ms Bhutto was travelling in when she was attacked, interviewed witnesses and scoured the crime scene, but have made no public statement.

President Pervez Musharraf met members of the investigation team on Tuesday and told them they were free to conduct their probe and 'no one will interfere in their affairs', Interior Ministry spokesman Javed Iqbal Cheema said.

But Bilawal said: 'Already so much forensic evidence has been destroyed.'

Hours after the attack on Ms Bhutto, firefighters with high-pressure hoses washed down the scene, a move that Mr Musharraf has since called a mistake.

ASSOCIATED PRESS