TEHRAN - Police used teargas against thousands of supporters of opposition leader Mir-Hossein Moussavi during a mourning march Sunday in central Tehran, eyewitnesses said.

Eyewitnesses said police used teargas after clashes between them and demonstrators.

Moussavi’s supporters had gathered to commemorate the anniversary of the death of Ayatollah Mohammad Beheshti, who was killed in a bombing on June 28, 1981. He was a former head of the judiciary and head of the Iranian mosque in the northern German city of Hamburg.

The gathering was also used as an opportunity to mourn the victims of recent protests.

Tehran’s governor’s office had banned such public gatherings in light of recent unrest in Iran following allegations of fraud in the June 12 presidential elections.

Mourners had gathered inside and outside the mosque, as well as in nearby streets, shouting, “Beheshti, where are you, Mir-Hossein has been left alone.”

Police forces had been deployed at the mosque venue and in nearby streets. Eyewitnesses said that both police and demonstrators at the mosque tried to refrain from provoking one another.

It is not yet clear whether the police could disperse the crowd or if the clashes were continuing.