A report by The Center for Public Integrity said the FBI and CIA made the positive identification through a technique called vein-matching.
Mohammed is also suspected of planning the Sept. 11, 2001, terrorist attacks on the United States. He previously claimed responsibility for the Wall Street Journal reporter's death, and the three-year Pearl Project prepared by faculty and students at Georgetown University in Washington confirmed his identity.
Pearl's death was taped and shown on the Internet and elsewhere, but the person who beheaded him wore a covering on his face. Through vein-matching (a technique that compared Mohammed's hand with that of the killer), authorities were able to corroborate Mohammed's previous confession.
Mohammed has not yet been charged in the 2002 killing to which he confessed nearly four years ago.
"I decapitated with my blessed right hand the head of the American Jew, Daniel Pearl, in the city of Karachi, Pakistan," Mohammed said in a Pentagon transcript released nearly four years ago. "For those who would like to confirm, there are pictures of me on the Internet holding his head."
Other findings in the report:
-- The Pearl Project identified 27 men who played a part in Pearl's execution. Many remain free.
-- Members of at least three militant groups took part in the crime, including a team of kidnappers led by British-Pakistani Omar Sheik, who offered to introduce Pearl to militant leaders, and a team of killers led by al-Qaida strategist Mohammed.
-- Mohammed told FBI agents in Guantanamo he personally slit Pearl's throat and severed his head to make certain he'd get the death penalty to exploit the killing for propaganda.
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