Sixty people were taken to various hospitals around the capital to be treated for injuries including burns and broken limbs, the health ministry said.
The clashes, which began yesterday evening near a police building where an armed pro-opposition group has been holed up for almost two weeks with several hostages, continued into the night.
There were also gun battles between police and this group yesterday.
Using truncheons, stun grenades and smoke bombs, police broke up a rally held in support of the gunmen, who are holding three medics.
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The gunmen -- supporters of fringe jailed opposition leader Zhirair Sefilyan -- stormed the police building on July 17, killing one officer, taking several more hostage and seizing a store of weapons.
They have since released all the police but on Wednesday began holding four medical staff who had entered the compound to treat some of their wounds.
One of the medics has since been released, while 24 gunmen are still inside.
Three of the gunmen were wounded in Friday's exchange of gunfire with police, with two taken to hospital under armed guard.
Council of Europe chief Thorbjorn Jagland urged both parties to "put an end to this dangerous situation without delay.