Lebanon's top Shia Muslim cleric, seen as a key figure in the founding of militant group Hezbollah, has died at the age of 74.
Grand Ayatollah Mohammed Hussein Fadlallah was regarded as Hezbollah's spiritual guide after its founding in 1982, something they both denied.
An implacable critic of the US, he had a wide following among Shias and backed the 1979 Islamic Revolution in Iran.
But he was known among Shias for his moderate social views.
He held particularly progressive views on the role of women in Islamic society.
The ayatollah had been ill for weeks, reports said, and was too frail to deliver his weekly sermon at Friday prayers.
He was admitted to hospital on Friday, reportedly suffering from internal bleeding.
As news of his death emerged, Hezbollah's TV station, al-Manar, interrupted its programming to broadcast his picture and recitations from the Koran.
Medical sources at Beirut's Behman hospital told news agencies Fadlallah had died, before a spokesman for the cleric emerged from the hospital to confirm the reports.
In the suburb of Haret Hreik, where the ayatollah preached at the al-Hassanayn mosque, black banners were hung in mourning and women wept openly in the street, the Associated Press reported.
Born to Lebanese parents in the Shia holy city of Najaf, in Iraq, Fadlallah moved to Lebanon in 1966 after completing his studies.
He won followers both in his home country and in Lebanon, extending his influence to Central Asia and the Gulf, Reuters reported.
He became regarded as the spiritual mentor to Hezbollah when it emerged as a Shia miliant group in 1982.
His views chimed with the strident anti-Israeli tone of the new movement, bringing him to the attention both of the Lebanese public and of Western intelligence agencies.
A 1985 car bombing in Beirut that killed some 80 people was widely thought to have been an attempt to assassinate the ayatollah.
The bombing was alleged to have been the work of the CIA, possibly in conjunction with regional intelligence agencies friendly to the US.
In his later years, Fadlallah distanced himself from Hezbollah over the group's links to Iran, but remained an outspoken critic of US policy in the Middle East and of Israel.
He welcomed the election of Barack Obama as US president in 2008, but last year expressed disappointment with his lack of progress in the Middle East, saying he appeared to have no plan to bring peace to the region.