POLICE are trying to trace the family of a teenage girl whose body was found outside a building in Sha Tin early yesterday. Police believe the 19-year-old girl fell from an upper floor of the tower block in Mei Lam Estate. An identity card was found on the girl but officers carrying out door-to-door investigations at Mei Wai House have been unable to find her family or anyone who knew her. The deceased was found lying outside the building shortly before 6.30 am and she was certified dead at the scene. No death note was found on her and police are still investigating the reasons behind the suspected suicide. A police spokesman said door-to-door inquiries were conducted in the building but failed to establish if the dead girl was a resident. ''We have not yet been able to locate her parents or any of her relatives but intensive investigations are continuing,'' he added.