Dubai, Dec. 21 : Iran has sent riots squads into the holy city of Qom to quell protests over the death of Grand Ayatollah Montazeri, the Islamic Republic''s most senior dissident cleric, the BBC reports.

Montazeri died of a heart attack at the age of 87. His grandson, Nasser Montazeri, said he had died in his sleep.

Ayatollah Montazeri was originally a follower of Ayatollah Ruhollah Khomeini, the leader of Iran''s Islamic Revolutionary, and was seen in the 1980s as his natural successor.

He opposed the dictatorial nature of the regime, particularly its mass executions of members of an opposition movement in the years before Ayatollah Khomeini''s death, and ended up one of its fiercest critics.

He spent five years in the late 1990s under house arrest, and even after his release he continued to oppose what he termed the regime''s repression. He attacked the re-election of President Mahmoud Ahmadinejad earlier this year.

Nevertheless, he remained in Qom, the holy city seen as the regime''s birthplace, and supporters were converging on the city from all over the country to attend his funeral, due to take place today/Monday.

Reformist websites last night were also reporting that crowds were gathering in Tehran.

By yesterday evening more security forces had been put on alert out of fear the funeral could become yet another focus for opposition rallies. (ANI)