An Iranian passenger aircraft has crashed killing everyone on board. The plane, a Tupolev operating between Tehran and the Armenian capital Yerevan, is believed to have been carrying 168 passengers and crew. It came down in northwestern Iran and local fire brigade officials were unable to find anyone alive at the crash site. According to the chief of police in the province of Qazvin the plane has been completely destroyed and is scattered in pieces in the surrounding countryside.Iran has a large Armenian community, and a representative from the airline, Caspian Airlines says most of the passengers on board were Armenian. A local official said the plane had reported technical problems and was attempting an emergency landing when it caught fire in mid-air. In the last decade Iran has suffered a number of plane crashes as both its civil and military fleets struggle to maintain, upgrade, and renew planes faced with international sanctions. In the most recent of those crashes a Boeing 737 belonging to a private Kyrgyz company Itek-Air, chartered by an Iranian company and bound for Iran, crashed at Bishkek airport, killing around 70 people, including members of a local teenage basketball team.