Islamabad, Pakistan (CNN) -- The Pakistani Taliban vowed on Thursday to kill Shakeel Afridi, the jailed Pakistani doctor accused of helping the CIA in the search for Osama bin Laden, a spokesman for the militant group told CNN.
"We will cut him into pieces when we find him," Pakistani Taliban spokesman Ehsanullah Ehsan told CNN by phone. "He spied for the U.S. to hunt down our hero Osama bin Laden."
Pakistani officials say Afridi is being held in a prison in the city of Peshawar in northwest Pakistan.
Last week a court in Pakistan's tribal region sentenced Afridi to 33 years in prison but a copy of the court order obtained by CNN shows Afridi was sentenced for alleged connections to the militant group Lashkar-e-Islam, not for helping Americans in the search for bin Laden.
Even so, the Pakistani Taliban says Afridi is the number-one target on its hit list.
On Wednesday the jailed doctor's brother told CNN he fears for Afridi's safety and called on the United States to help set him free.
"These allegations are false. They're baseless," said Jamil Afridi.
"My brother didn't do anything against Pakistan. If he helped the U.S., it was for the benefit of Pakistan. The American government should help us in any way it can."
Officials had told CNN Shekeel Afridi was charged with treason for spying for the United States. He was accused of helping the CIA locate bin Laden in his compound in Abbottabad through a fake vaccination campaign.
Bin Laden was killed in the subsequent U.S. raid on the compound in May last year.
At least one legal analyst said Afridi's sentence is a sham.
Islamabad-based lawyer Shahzad Akbar questioned the legitimacy of the court proceedings, since the punishment was handed down by a tribal court in Khyber even though the alleged offense occurred in Abbottabad.
The Afridi verdict sparked anger in the United States and further strained relations between Washington and Islamabad. The tensions surfaced as Congress debated aid to Pakistan in several bills.
In the National Defense Authorization Act, senators agreed last week to withhold Pakistan's part of a $1.75 billion aid package because of outrage over Afridi's case and the continued blockade of NATO supply routes into and out of Afghanistan.
Another bill in the Senate Appropriations Committee withheld $33 million in aid to Pakistan for similar reasons.
Pakistani Interior Minister Rehman Malik has said cutting aid is a U.S. prerogative, but added: "I think the U.S. should not forget we are a victim in this war on terror and we're suffering for the international community, too."
Journalist Nasir Habib contributed to this report.