The top al-Qaida operative accused of masterminding the Sept. 11 attacks either killed or took part in the murder of American journalist Daniel Pearl, Pakistan's president has alleged for the first time. President Gen. Pervez Musharraf's claim, made in his memoirs released this week, could now be used to try clear one of Pearl's four convicted killers, who is appealing his death sentence, the prisoner's lawyer said Wednesday. Musharraf accused Khalid Sheikh Mohammed of taking part in Pearl's killing in Pakistan's largest city, Karachi, following the journalist's kidnapping on Jan. 23, 2002. Mohammed was arrested in Pakistan in 2003 and...