TEHRAN (Reuters) - Big crowds of mourners chanted anti-government slogans during the funeral of Iran's leading dissident cleric, Grand Ayatollah Hossein Ali Montazeri, in the holy city of Qom on Monday, websites reported.
Montazeri, who died on Saturday night aged 87, was viewed as the spiritual patron of an opposition movement that blossomed after a disputed presidential election in June and has proved resilient despite repeated efforts to suppress it.
The reformist website Jaras said hundreds of thousands of people joined a procession for Montazeri, an architect of Iran's 1979 Islamic revolution that toppled the U.S.-backed shah. He later became a fierce critic of its present hardline leadership.
"They were shouting slogans in his support and also in support of (opposition leader) Mirhossein Mousavi," Jaras said.
Ayande website, seen as close to conservative politician Mohsen Rezaie, said: "The burial ceremony has come to an end and the crowd are in the streets around the shrine demonstrating and shouting anti-government slogans."
The reformist Kaleme website said crowds carrying "green symbols" had chanted: "Today is the day of mourning and the green Iranian nation is the owner of this mourning", referring to the colour adopted by the opposition.
The reports could not be verified independently. Foreign media have been banned from reporting on protests and also from travelling to Qom for Montazeri's funeral.
Riot police were out in force to in Qom, 125 km (80 miles) south of Tehran for the funeral of the senior Shi'ite cleric who had been a thorn in the side of the establishment during his life.
His death of a heart attack occurred at a tense moment when the government was seeking to choke off any attempt by its opponents to use the run-up to the Shi'ite religious occasion of Ashura to stage large-scale rallies.
Now the seventh-day mourning ritual for Montazeri will coincide with Ashura on Sunday, perhaps amplifying the intensity of any protests. The Islamic nature of the occasion makes it harder for the authorities to keep people off the streets.
The internal upheaval, highlighted by Montazeri's arguments the leadership had lost its legitimacy, has complicated a long-running dispute over Iran's nuclear programme, which the West believes may have military, not just civilian purposes.
Mousavi, the main opposition leader reached Qom and had given Montazeri's family his condolences, the reformist website Kaleme said. But security forces were reported to have intercepted other activists on their way to the city.
Opposition figures declared a national day of mourning for Montazeri, who was named in the 1980s to succeed revolutionary leader Ayatollah Ruhollah Khomeini, but was shunted aside after he criticised mass executions of prisoners.
Khamenei, who succeeded Khomeini after he died in 1989, expressed his condolences, but said he asked God to forgive Montazeri over a "difficult and critical test" that he faced towards the end of Khomeini's life", ISNA news agency said. Khamenei made clear he believed Montazeri failed the test.
The Ministry of Culture and Islamic Guidance told newspapers in Tehran not to print front-page photographs of Montazeri or carry condolence messages, except for Khamenei's, the Kaleme and Parlemannews websites said. No official comment was available.
Khomeini's grandson, Hassan Khomeini, a cleric, paid tribute in his condolence message to a man he said had "spent many years of his honourable life on the path of advancing the high goals of Islam and the Islamic revolution", ILNA news agency reported.
Human rights activist and Nobel prize laureate Shirin Ebadi called Montazeri "the father of human rights in Iran".
President Mahmoud Ahmadinejad's re-election in a June vote that losing candidates Mousavi and Mehdi Karoubi said was rigged sparked the worst unrest in the Islamic Republic's 30-year history and split the political and clerical establishment.
In August, Montazeri said the authorities' handling of the unrest "could lead to the fall of the regime" and he denounced the clerical leadership as a dictatorship.
The authorities deny charges of electoral fraud and have portrayed the protests, quelled by Revolutionary Guards and Islamic militiamen, as a foreign-backed plot to undermine them.
"Montazeri was one of the chief spiritual and religious voices of the reformist movement," said Alireza Nader, Iran analyst at the RAND Corporation in Washington.
"His status as a source of emulation and his revolutionary credentials provided a cover of legitimacy for the reformists' political and social demands," Nader told Reuters.
"His death leaves an important vacuum, but there are other senior clerics who are also outspoken against the Ahmadinejad administration and demands for political reform. His absence will not necessarily lead to a weakening of the opposition."
(Writing and additional reporting by Alistair Lyon; Editing by Matthew Jones)