Police are investigating whether foul play was involved in the death of an elderly woman whose body was found floating in a nullah – a drainage channel – in Tin Shui Wai on Monday morning. Police and fire department officers were called in when the body was sighted shortly before 9.45am outside Tin Shui Estate by a male passer-by. Firefighters pulled the body out of the water. Police said no identification documents were found on the body, but there were injury marks. It is understood that an elderly woman was reported missing by her family on Sunday. A police spokeswoman said officers were still trying to establish the identity of the woman. Crime squad officers from the Yuen Long police district are heading the inquiry.