A group of armed men from an opposition group stormed a district police headquarters and exchanged fire with police in the Armenian capital, Yerevan, early in the morning on July 17, the National Security Service (NSS) said in a statement.



The NSS said that a police officer was killed and two other were wounded in the shootout in Erebuni police station.



Earlier the security service had said the attackers are holding several hostages in the police headquarters, adding “negotiations are under way to release them peacefully.” Security officials say two of the hostages have been released.



The opposition group Founding Parliament issued in a statement demanding the release of the group’s leader Zhirayr Sefilian, who was arrested last month on charges of seeking to overthrow the government by force.



Varuzhan Avetisian, a spokesman for the group, has also announced that "they are starting a rebellion" and attempt to “overthrow the government” and “release political prisoners.”



Police have cordoned off the area, with armored vehicles blocking off the road to the police station. The NSS statement said that law enforcement agencies were functioning as normal to uphold public safety.



Meanwhile, opposition lawmaker and outspoken government critic Nikol Pashinyan visited the police station and spoke with the attackers.



Pashinyan, the leader of the newly established Civic Agreement opposition party, said one of the attackers inside the police station was critically wounded in the head.



He also said a policeman, who was feeling unwell, has been released by hostage-takers.



The Founding Parliament group frequently stages street protests in Yerevan, demanding the resignation of President Serzh Sarkisian.



The group is particularly critical of the way the government has been handling a long-running conflict in Azerbaijan's breakaway region of Nagorno-Karabakh, the territory claimed by both Armenia and Azerbaijan.