Federal investigators were trying to determine what role Ahmed Abdel Sattar had in preparing a letter of introduction for the men who killed Gen. Ahmed Shah Massood, the leader of the Northern Alliance, the source said Monday, speaking to The Associated Press on condition of anonymity.
The letter may have been used by two men posing as journalists when they killed Massood on Sept. 9, said the source who is familiar with the investigation. Massood died from injuries after a bomb hidden inside a television camera detonated.
The New York Post first reported last month that investigators suspected Sattar helped a London man, Yassir Al-Sirri, write a letter vouching for the men as journalists and requesting an interview with Massood.
It's not clear whether Sattar knew the letter might be used in an assassination plot.
Al-Sirri and Sattar, were named as co-defendants last month in an unrelated terrorism indictment in New York. Al-Sirri has also been charged in London with conspiring to murder Massood last Sept. 9.
Sattar, a 13-year veteran of the U.S. Postal Service, has not been charged in connection with the assassination. His lawyer, Kenneth Paul, declined to comment.
On Monday, The Washington Post reported that investigators had heard a summer 2001 conversation about the letter during hundreds of hours of wiretaps involving Sattar.
The assassination of Massood was a blow to the Northern Alliance, which had long fought the Taliban in Afghanistan. U.S. officials have speculated that the assassination was a pre-emptive strike against the opposition leader just days before the Sept. 11 terror attacks against New York and Washington.
Sattar, Al-Sirri and two others were charged last month with helping an imprisoned Muslim cleric Sheik Omar Abdel-Rahman spread terrorist messages from the prison where he is serving a life sentence for plotting to blow up New York City landmarks.
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