The 49-year-old is thought to be Lee Peacock, who officers were trying to trace as part of an investigation into the murders of Sharon Pickles and Clinton Ashmore.
He was found on Wednesday on a canal barge in Ferrymead Avenue, Ealing, suffering serious injures believed to be self-inflicted. He was rushed to hospital in a life-threatening condition.
Police earlier released CCTV images of Peacock as part of the investigation. He had last been seen at North Wembley station on the evening of August 19.
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The same evening, at 9.30pm, police were called to an address in Ashbridge Street, Westminster, where Ms Pickles, 45, was found dead.
At 2.15am on Friday, Clinton Ashmore, 59, was found dead at an address in nearby Jerome Crescent.
Both died from a stab wound to the neck and the two incidents have been linked. It’s believed Peacock knew both victims.
Scotland Yard said in statement: “Shortly before 17.55pm on Wednesday, officers visited a canal barge in the vicinity of Ferrymead Avenue, Ealing as part of an ongoing investigation.
“Inside they found a man who officers are confident is 49-year-old Lee Peacock. He has previously been named as a person they were keen to locate in connection with an investigation into the murder of two people in Westminster on Thursday, August 19.
“The man has sustained serious injuries, which at this stage it is believed were self-inflicted. London Ambulance Service paramedics and the London Air Ambulance were called. The man has been transported to hospital where his condition is believed to be life threatening.
“The Met’s Directorate of Professional Standards was informed and the incident was referred to the Independent Office for Police Conduct who have indicated that they will be conducting an independent investigation.”
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