(RFE/RL) -- Iranian security forces are reported to have clashed with opposition protesters using a religious ritual to stage fresh antigovernment demonstrations.
Witnesses told RFE/RL's Radio Farda that police and Basij militia were out in force in Tehran and other cities, including Mashhad, Qom, Hamedan, and Najafabad and preventing protesters from congregating in large numbers. Other reports quoted witnesses as saying police fired tear gas and used batons to disperse the demonstrators.
The incidents come as Iran marks a Shi'ite religious festival, Ashura, commemorating the death of a grandson of the Prophet Muhammad in the seventh century.
Its culmination on December 27 coincides with the seventh day since the death of Grand Ayatollah Hossein Ali Montazeri, one of Iran’s most prominent dissidents and an outspoken critic of the government.
An eyewitness from the western city of Najafabad, who didn’t want to give his name, told Radio Farda that a group of people chanted slogans supporting Montazeri as well as the opposition Green Movement and that there were "a few clashes today in Najafabad with Basijis and security forces" and that the situation in Najafabad is now "tense."
"Security forces are not allowing these people to move towards the city center where they were supposed to gather," he added. "There are increased security measures also in other smaller towns around Najafabad, as if martial law has taken effect here."
A resident from the town of Hamedan said there was a heightened police presence "in the city center and key locations" in the city. In one neighborhood, "I saw the plainclothes forces and Basijis were talking on their handheld radio, and wherever people are gathering, Basijis go there and disperse them."
A resident of the eastern city of Mashhad, who did not want to give her name, told Radio Farda that a two-day ceremony was being held by Montazeri supporters in the city to commemorate the dissident cleric.
She said security forces were closely monitoring the gathering and that they arrested a young man as he was leaving the ceremony, and that the security forces "have installed video cameras there to record who was coming in and out of the building."
Opposition websites "Jaras" and "Rahasabz" said security forces also broke into a building in Tehran housing the ISNA news agency after some protesters sought shelter there.
The report could not be independently verified, as foreign media have been banned from covering protests.
Iran's police chief, Esmail Ahmadi Moghaddam, had warned that police would harshly confront any nonreligious gatherings.
Today's protests are the latest to have flared since June's disputed presidential election, which the opposition says was rigged in favor of incumbent Mahmud Ahmadinejad.
In recent months, Iranian opposition supporters have used symbolic days and religious holidays to stage antigovernment protests.
RFE/RL's Radio Farda contributed to this report. With news agency material