Manchester police have today renewed their appeal for witnesses after the discovery of a body in a city centre canal.

At 2.10am on Friday police were called to Ducie Street, Manchester following a report that a man had been seen in the canal.

The area is used by men looking for sex with other men but lead investigating officer Detective Superintendent Mark Powell has reassured witnesses who may be reluctant to come forward.

Officers attended with the underwater search team and the body of a man was later found.

The man has not yet been identified but a post-mortem examination was held yesterday and revealed the cause of death was drowning. The post-mortem did not show any obvious signs of trauma.

Police are keen to speak to anyone who was in the area from 10pm to 2.30am, and are particularly keen to speak to a man who made a phone call to the emergency services when he saw the body in the water, but did not leave any contact details.

Detective Superintendent Mark Powell said: “We are still in the early stages of our inquiry and our efforts are being centred on identifying this man and his movements on the night of Thursday 2nd October 2008 leading up to his death in the early hours of the next day.

“It is vital that anyone who has any information comes forward so we piece together exactly what happened.

“We know that this particular area of the canal is sometimes used by men looking for sex with other men and therefore some witnesses may be reluctant to come forward. But you could hold vital information which could help us build up a picture of what happened to this man and I would therefore urge you to come to us.”

Emphasising that the police will exercise discretion when speaking to witnesses, he added: “We are not interested in why you were there, only what you saw. You can come to us in confidence and we will treat you with discretion and respect.”

Anyone with information about the incident is asked to call the Major Incident Room at Wythenshawe on 0161 856 4721 or Crimestoppers anonymously on 0800 555 111.