An Egyptian engineer who was serving 15 years in prison for spying for Israel died in his cell in Cairo, a security official said on Monday. Jail wardens found Shereef Fawzi Mohammed el-Filali, 41, dead in his cell in Torah prison when they went to wake him up early Monday morning, the security official said on condition of anonymity because he was not authorized to speak to the media. Prison doctors determined that el-Filali died of heart failure, and his family was asked to come collect his body, according to the official. In March 2002, a state security court convicted el-Filali of spying for Israel and sentenced him to 15 years in prison with hard labor. El-Filali had pleaded innocent to charges of providing information about Egypt's military, economic, political and tourism situation with the intent of harming the country's national interests. Israel denied that el-Filali was its spy and said it did not have connection to the case. A court acquitted el-Filali in his first trial in June 2001, with the judges saying the state had proved its case, but that el-Filali was not guilty because he had come forward about his actions. Egyptian President Hosni Mubarak ordered a retrial after the acquittal caused public outcry in Egypt. A Russian co-defendant, Gregory Cevets, was found guilty of espionage and recruiting el-Filali and was sentenced in absentia at the time to 25 years in prison with hard labor.