Thousands of Egyptian Coptic Christians have joined a funeral mass in Cairo for their patriarch, Pope Shenouda the Third, who died of illness on Saturday at the age of 88.

Mourners, many of them in tears, packed St. Mark's Cathedral for the service, also attended by representatives of Egypt's ruling military council and prominent political figures. Priests recited prayers over Shenouda's body as it lay in an open coffin, dressed in robes and a gold crown.

After the mass, the pope's coffin was taken to a military air base for a flight to a desert region northwest of Cairo, home to a 4th century monastery where he had asked to be buried.

The late Egyptian President Anwar Sadat exiled Shenouda to the desert monastery in 1981 after the pope accused the Sadat government of failing to take action against Muslim extremists. Former President Hosni Mubarak ended Shenouda's exile in 1985.

Shenouda led Egyptian Copts through periods of tension with the country's Muslim majority. Islamist militants bombed a Coptic church in Alexandria in 2011, killing 23 people. The rise of political Islam in Egypt since the ouster of Mr. Mubarak in a popular uprising last year has left Egyptian Copts increasingly anxious about their future.

Shenouda was born Nazeer Gayed, entering the priesthood and later a monastery as a young man. He was elected Coptic pope in 1971.

Egypt's Copts make up about 10 percent of the country's population of 80 million. Historians say the Coptic church is one of the oldest in the world. It traces its founding to the Apostle Mark, who is said to have introduced Christianity to Egypt in the First century.