A man who police initially believed was stabbed on Westminster Bridge actually suffered a cardiac arrest, the Metropolitan Police have confirmed.

Officers were called at about 10.45am on Sunday after a fight broke out on the bridge in central London.

Met Police attended with the London Ambulance Service and London’s Air Ambulance, and found a man suffering from a cardiac arrest.

The force said initial reports suggested the man had been stabbed, but further inquiries confirmed this was not the case.

Investigations are ongoing and the man remains in hospital in a critical condition.

Three people have been arrested on suspicion of attempted murder, and one person has been arrested on suspicion of affray. Two of those arrested have been taken to hospital with head injuries.

Police said they are keen to hear from anyone who was in the area at the time and may have witnessed the incident.

Anyone with information or footage should contact police on 101, quoting CAD 2468/24NOV, or contact Crimestoppers anonymously on 0800 555 111.