Six people have been killed after suspected drug traffickers shot down a small plane in Urique, a city in the northern Mexican state of Chihuahua, state officials said.The victims were aboard an air taxi that was on its way from the northwestern state of Sinaloa to Chihuahua when it was shot down by drug traffickers, Spanish news agency Efe reported on Wednesday.The reason why the plane was shot down has not been determined, the Chihuahua Attorney General's (AG) Office said."After searches, patrols and sweeps in towns outside the city of Urique, a Cessna-type plane was found on Tuesday afternoon in the Arroyo de Tubares, located in Las Cieniguitas, on the border of Chihuahua and Sinaloa," the AG's office said in a statement.The bodies of six men, including pilot Eleazar Ramirez Perez, were found at the crash site and taken to the coroner's office.The other five victims of the shootdown have not been identified and investigators are trying to obtain more evidence, the AG's office said.