Helicopters hovered overhead as about 200 protesters gathered at Haft-e-Tir Square Monday. Hundreds of anti-riot police quickly put an end to the demonstration.
Witnesses said police at the scene tried to prevent any gathering, even small groups. At the subway station at Haft-e-Tir, police did not allow anyone to stand still, asking them to keep walking and separating people who were walking together.
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http://accesswdun.com/article/2009/6/221281