TEHRAN, Iran: Iran’s Ayatollah Hossein Ali Montazeri has died of an illness Saturday night, his office in the holy city of Qom said Sunday December 20.

"He was diabetic and had been using insulin for years... he had also some lung problems and asthma. In fact he was suffering from several diseases," his doctor told state television.

Funeral of Montazeri, 87, will be held on Monday and he will be buried in the shrine of Hazret Fatimeh Masoumeh (peace be on her) in the holy city of Qom.

Foreign media are banned from covering the ceremony.

"Thousands of people from Isfahan, Najafabad, Shiraz and other cities have left for Qom to take part in his funeral," Parlemannews.ir, the website of parliament's reformist faction, reported.

According to the opposition website Rahesabz.net, students in the Tehran University immediately began mourning once they heard news of the death of the grand ayatollah.

Ayatollah Montazeri was born in 1922 to peasant parents in the city of Najafabad, south of Tehran. He studied theology in Isfahan and later continued his education in Qom under the Islamic Republic's founder, Ayatollah Ruhollah Khomeini. He later became active in the anti-Shah movement and was jailed in 1974. He was released in 1978 - a year before the Islamic Revolution led by Khomeini.