A state of emergency has been declared in Armenia's capital on the 11th consecutive day of protests against an allegedly rigged presidential election.
President Robert Kocharyan signed the decree "to prevent a threat to constitutional order".
It came after police fired in the air to disperse demonstrators. Some reports suggest a number of casualties.
Prime Minister Serzh Sarkisian won the 19 February vote against opposition challenger Levon Ter-Petrosian.
Mr Ter-Petrosian says he is under house arrest.
BBC NEWS: Armenia declares emergency rule