Iranian opposition Web sites called for rallies Thursday in Tehran, despite the government's ongoing crackdown that has included arrests of university professors, journalists and ordinary citizens.
Witnesses tell VOA (Persian News Network) that a larger-than-normal crowd of about 13,000 people flocked to Tehran's main cemetary Thursday, in part to mourn the victims of Iran's post-election violence.
Residents in the capital say on a normal day some 9,000 people visit the Behesht-e Zahra cemetary, which holds graves for many of the victims of the Iran-Iraq war.
There were no immediate eyewitness reports of organized protests either in the cemetary or elsewhere in the capital. Reformist presidential candidate Mehdi Karroubi earlier had canceled a mourning ceremony set for Thursday.
On Wednesday, police forcibly dispersed hundreds of protesters attempting to gather near Iran's Parliament.
The government has maintained a heavy police presence in the streets to disperse crowds, especially since Saturday's violence between authorities and protesters killed at least 10 people. Hundreds more have been arrested.
In a statement posted on his official Web site Thursday, opposition leader Mir Hossein Mousavi said at least 70 university professors were detained after meeting with him on Wednesday. He added that his access to supporters has been highly restricted, and he is facing pressure to withdraw his election challenge.
Mr. Mousavi, who lost to incumbent President Mahmoud Ahmadinejad in the June 12th vote, has alleged massive fraud in the election. But Iran's supreme leader and the Guardian Council say the results will not be reversed.
Meanwhile, President Ahmedinejad accused U.S. President Barack Obama of mirroring the hardline stance of his predecessor, George W. Bush.
President Obama on Tuesday said he was "appalled and outraged" by the post-election government crackdown.
Iran's disputed vote has triggered the country's greatest unrest since the 1979 revolution.
Grand Ayatollah Hossein Ali Montazeri warned Iranian leaders Thursday that continued suppression of dissent could destabilize the regime. Montazeri was once seen as a possible successor to the late Ayatollah Khomeini.
The official death toll is 17 people, but witnesses to clashes say it is much higher. State media also reported Thursday that eight members of the pro-government Basij militia were killed. Figures cannot be verified because Iran has severely restricted news organizations' abilities to report from the country.