Detectives investigating the suspicious death of a man at Shadwell Basin are renewing their appeals for help in tracing someone who may have tried to save his life.

Ibrahim Gharib, 20, drowned on March 18 last year after falling into the water. He had been with a 17-year-old female friend at the waterside and officers believe he may have been involved in a confrontation with another group of people around 9.30pm.

Police have now released CCTV images of a man they believe dived into the water in an attempt to save his life.

He was caught on CCTV at Sadwell DLR station at 9.15pm, shortly before Ibrahim fell into the water and police are anxious to trace him as they believe he may be a vital witness.

By the time police arrived at the scene the man, believed to be eastern European, had already left.

Ibrahim’s body was recovered from the water the following morning. A post-mortem showed that he had drowned.

A �20,000 reward is on offer for information leading to the identification, arrest and prosecution people responsible for Ibrahim’s death.

An incident room is open at Barking under detectives from the Homicide and Serious Crime Command.

Police are appealing for anyone who knows who the man caught on CCTV to call the incident room on 020 8345 3734 or Crimestoppers anonymously on 0800 555 111.

Four people have been arrested in connection with the inquiry and have been released on police bail until next month.