Peshawar - Pakistani authorities have sentenced a doctor accused of helping the CIA find Osama bin Laden to 33 years in jail on charges of treason, officials said, a move that drew angry condemnation from United States officials already at odds with Islamabad.

Shakil Afridi was accused of running a fake vaccination campaign, in which he collected DNA samples, that is believed to have helped the American intelligence agency track down Bin Laden in a Pakistani town.

The al-Qaeda chieftain was killed in a unilateral US special forces raid in the town of Abbottabad in May last year.

“Dr Shakil has been sentenced to 33 years imprisonment and a fine of 320 000 Pakistani rupees,” said Mohammad Nasir, a government official in the north-western city of Peshawar, where the jail term will be served. He gave no further details.

Afridi is the first person to be sentenced by Pakistani authorities in the Bin Laden case.

The sentence was handed down under tribal laws, which unlike the national penal code do not carry the death penalty for treason.

US officials and lawmakers said Afridi deserved only praise.

“We continue to see no basis for these charges, for him being held, for any of it,” State Department spokesperson Victoria Nuland told reporters, declining specific comment on the 33-year sentence given to Afridi.

A senior US official with knowledge of counter-terrorism operations against al-Qaeda in Pakistan said the doctor's actions “helped save Pakistani and American lives”.

“His activities were not treasonous, they were heroic and patriotic,” said the official.

Two senior US senators called the ruling “shocking and outrageous” and urged Islamabad to pardon and release the doctor immediately.

“He should be praised and rewarded for his actions, not punished and slandered,” Republican Senator John McCain and Democratic Senator Carl Levin said in a statement.

“Dr Afridi's continuing imprisonment and treatment as a criminal will only do further harm to US-Pakistani relations, including diminishing Congress's willingness to provide financial assistance to Pakistan,” they said.

Bin Laden's long presence in Pakistan - he was believed to have stayed there for years - despite the worldwide manhunt for him raised suspicions in Washington that Pakistani intelligence officials may have sheltered him.

Pakistani officials deny this and say an intelligence gap enabled Bin Laden to live here undetected.

No one has yet been charged for helping the al-Qaeda leader take refuge in Pakistan. A government commission tasked with investigating how he managed to evade capture by Pakistani authorities for so long is widely accused of being ineffective.

Afridi's imprisonment comes at a sensitive time, with both sides engaged in difficult talks over re-opening Nato supply routes to US-led troops in Afghanistan.

Senior US officials had made public appeals for Pakistan, a recipient of billions of dollars in American aid, to release Afridi, detained within weeks of the raid that killed Bin Laden and strained ties with Islamabad.

In January, US Defence Secretary Leon Panetta said in a television interview that Afridi and his team had been key in finding Bin Laden, describing him as helpful and insisting the doctor had not committed treason or harmed Pakistan.

US Congressman Dana Rohrabacher introduced legislation in February calling for Afridi to be granted American citizenship and said it was “shameful and unforgivable that our supposed allies” charged him. - Reuters