Since Sunday's bloody clashes which left eight protesters dead, 500 people have been arrested, according to Iran's police Chief Gen. Ismail Ahmadi Moghaddam. This number could be higher because hardline Basij militiamen and intelligence agents may have apprehended more people on their own, Moghaddam told IRNA.
The pro-green web site Jaras says that as many as 1,510 people are being held and according to HRNA (Human Rights Activist News Agency) the notorious Evin prison is overflowing.
"According to reports from a human rights group in Iran, the massive number of arrests in the past three days forced Evin prison authorities to build a temporary detention center inside the prison." HRNA reported.
Photographs published on-line Tuesday purportedly showed people gathered outside the prison hoping for news of relatives inside.
Among those arrested in the last few days was the sister of Iranian Nobel Peace Prize winner Shirin Ebadi. Makhmalbaf views this is part of the new intimidation tactics being used by the regime. "They arrested the sister of Shirin Ebadi to put her under pressure. This is the style of the Mafia," he said.
"They always change their tactic and strategy. On Ashura they were killing people and targeting people," referring to the religious holiday earlier this week. "This is new, targeting. They are telling people we can kill you."
Makhmalbaf believes the government deliberately targeted Mousavi's nephew, a claim the police have denied.
They are not, however, shying away from threatening violence against the protesters. "The days of tolerance are over and the police will have a severe encounter with riot makers," Moghaddam warned Tuesday.
Despite these threats several members of The Green Movement's online community are calling for a retaliatory rally tomorrow.
One blog entitled "Be Alert! Something is in the air" warns protesters to be mindful of the government's possible heavy handedness, but to continue with well organized non-violent protests.
"Unfortunately the current situation is far from normal. In addition to rumors and innuendos about the potential arrests of Mousavi and Karoubi (which have of course not been confirmed), there is a high chance of a stupid move or coup by the government. Let's remember that this government has nothing left to lose," the blog warned.
The Associated Press, Reuters and ABC News' Desiree Adib contributed to this report