Iranian security forces have reportedly fired tear gas at anti-government protesters attending a rally in Teheran.

A website linked to the opposition, Kaleme, claimed that policemen and people [dressed] in civilian clothes tried to disperse the crowd with the gas.

BBC reported that security officers were stationed at key points in the city for the purpose of preventing the rally from taking place.

The disturbance comes a day after Iran’s two most prominent opposition leaders Mir Hossein Moussavi and Mehdi Karroubi (and their wives) were reportedly taken from their homes and imprisoned in the Heshmatieh military prison in eastern Tehran.

(However, state sources deny this report and claim the two men are still in their residences under house arrest).

Protesters reportedly chanting slogans in support of Mousavi and Karroubi, while castigating the ruling regime of President Mahmoud Ahmadinejad, whose disputed re-election in 2009 led to nationwide demonstrations.

Mousavi and Karroubi have called for more anti-government demonstrations in Iran, having been inspired by the recent upheavals in Tunisia and in Egypt.

Foreign media has been banned from covering the ongoing turmoil in Iran, making it impossible to verify news reports provided by opposition groups.

The US and Germany criticized Iran for the alleged arrests of the two leading opposition figures.

Foreign Ministry spokesman Ramin Mehmanparast said that the West had no right to interfere with Iran and that western nations should ”listen to the voice of the majority, rather than a few of them. These are internal affairs and no country has and will have any right to interfere in the decisions by the judiciary.”

Meanwhile, Iran’s opposition parties plan more demonstrations, with the next one scheuduled for March 15.