A post-mortem examination on a suspected mugger who died after being detained by members of the public was inconclusive, police have revealed.

Further tests will now take place to establish the cause of death of the man, in his 30s, who fell ill after the incident on Thursday in Holloway Road, Holloway.

A police spokesman said officers were called to the scene at approximately 10.45pm after a resident reported an alleged robbery in the street.

By the time they arrived, members of the public had detained the man, who was then handcuffed by police, but not placed under arrest.

He became unwell and officers called the London Ambulance Service, but he died in hospital at 12.12am the following day.

The police’s homicide and major crime command has launched an investigation.

An incident room has been opened at Lewisham police station and enquiries are being led by Det Ch Insp Graeme Gwyn.

The Directorate of Professional Standards attended the incident and a referral was made to the Independent Police Complaints Commission, which has begun its own independent investigation.

The police spokesman said officers believe they know the identity of the man and his next-of-kin have been informed, but they await formal identification.

Anyone with information is urged to call the incident room on 020 8721 4805.