Sheikh surrendered in March 2003, and was sentenced to death for kidnapping and murdering Pearl, who was in Pakistan researching a story on Al Qaeda's role in the 9/11 attacks.
But in his recently released book, In the Line of Fire , Musharraf says that "only later did I realise that Omar Sheikh had panicked because the situation had spiralled out of his control."
"The man who may have actually killed Pearl or at least participated in his butchery, we eventually discovered, was none other than Khalid Sheikh Mohammed, al Qaeda's number three. When we later arrested and interrogated him, he admitted his participation," he says. Khaled Sheikh Mohammed is the main accused in the 9/11 terrorist strikes.
Omar Sheikh was among the three terrorists released from Indian custody in exchange for the hostages of the hijacked Indian Airlines plane, IC 814, in December 1999.
Sheikh's lawyer, Rai Bashir, told reporters that he would use extracts from the book to seek a fresh hearing and trial for his client, a British citizen of Pakistani origin.
"After reading the book, if I feel necessary, I will quote the book in my arguments in favour of my client. It can be used as evidence," Bashir was quoted as saying.
Three others who have been sentenced to 25 years in jail for their involvement in the brutal slaying of the American reporter have also appealed to the superior courts.
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