PESHAWAR, Pakistan — A Pakistani lawyer has filed an appeal against the conviction of a doctor jailed after helping the U.S. find Osama bin Laden.

Samiullah Afridi says he filed the appeal Friday for Dr. Shakil Afridi, sentenced to 33 years in prison under Pakistan's tribal justice system.

The case has worsened Pakistan's already tense relations with the U.S.

Afridi was arrested last May after U.S. Navy SEALs killed bin Laden in the garrison town of Abbottabad.

Afridi ran a fake CIA vaccination program to obtain DNA samples from relatives to confirm the al-Qaida leader's presence.

The tribal court convicted Afridi for treason over ties to a banned militant group, not for helping the U.S. The militants denied he was a member and threatened to kill him for working with the U.S.

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