At least two people were injured in an explosion at a police station in the Armenian capital Yerevan on Sunday, after three armed men forced their way in to demand the release of some 50 people arrested earlier in the day, according to police. Two of the attackers were injured when a hand grenade detonated, police spokesman Narek Sarkisyan was quoted as saying by Russian state news agency TASS. They were brought to hospital for treatment. The third attacker was overpowered and disarmed by special forces inside the station in Yerevan’s Nor-Norka district after lengthy, unsuccessful negotiations…