Greek police say a riot by illegal immigrants at a detention centre near Athens has been contained. Detainees had set fire to their bedding and attacked guards while dinner was served at the Amygdaleza facility northeast of the capital . It followed an announcement that detention time would increase from 12 to 18 months. Also, electricity had been cut because of maintenance work, leaving the containers, where around 1,700 migrants are held, without air conditioning. Riot police used chemicals and stun grenades to quell the protest. Police said at least 10 prison guards were injured, none of them seriously. It was not clear if any detainees were injured. More about: Athens, Greece, Illegal immigration