Several thousand demonstrators calling for the Armenian prime minister’s resignation protested in the square outside the government's headquarters on Thursday.
Some clashed with police, and officers arrested 21 people.
Prime Minister Nikol Pashinyan has been a target of popular discontent since November, when he signed an agreement to end fighting in the separatist territory of Nagorno-Karabakh. The agreement ceded land in Azerbaijan that had been under Armenian control since the mid-1990s. The 44 days of fighting left some 6,000 people dead.
Pashinyan has refused calls to step down but raised the possibility of holding an early election.
