Police in northern England are trying to identify a man whose body was found in a sewage tank in Middlesbrough. Investigators said Monday the man appeared to be between the ages of 21 and 40, The Northern Echo reported. He died between three weeks and three months before his body was found Oct. 14 by Northumbrian Water employees at the Cargo Fleet pumping station. The man was 5 feet 9 inches tall, weighed about 168 pounds and had dark hair. Investigators said he had good teeth, although some of them had been extracted. Detective Inspector Cath Galloway said the death is being treated as unexplained because there were no signs of violence on the body. \"There will be a family out there missing a son, brother or father and my investigation is focused on trying to find out who this man is as soon as possible,\" Galloway said. \"Anyone who may be concerned about a friend, relative or neighbor who they may not have seen for a number of weeks, I would like them to come forward as soon as possible.\"