Lebanon's Grand Ayatollah Sayyed Mohammed Hussein Fadlallah,one of Shia Islams highest religious authorities and an early mentor of the militant group Hezbollah,died in a Beirut hospital on Sunday,his family said. Fadlallah,who was 74,had a wide following beyond Lebanons Shias. He had been too frail to deliver his regular Friday prayers sermon for weeks,and had been in hospital since Friday suffering from internal bleeding. Crowds gathered at his Hassanein mosque in southern Beirut to pay condolences,and Hezbollah said it would mark his death with three days of mourning. Fadlallah was a supporter of Irans Islamic Revolution and the spiritual leader and mentor of the Shia guerrilla group Hezbollah when it was formed after Israel invaded Lebanon in 1982. A fierce critic of the US,which formally designated him a terrorist,Fadlallah used many of his Friday prayer sermons to denounce US policies in West Asia,particularly its alliance with Israel.