James Riley, 28, pleaded guilty at a hearing to trying to kill Ellie Moxham on 10 November last year.

Riley, from Preston, Lancashire, had previously denied the offence and was facing a trial at Manchester Crown Court scheduled for next week.

But he changed his plea at the pre-trial review hearing.

He was further remanded in custody by Judge Patrick Field KC after entering his plea via videolink from HMP Forest Bank in Salford.

The officer will be sentenced on 12 January.

Greater Manchester Police previously said officers were called to a report of concern for the welfare of a woman at a hotel in Brook Street, Manchester, at about 11.30pm on the Thursday night in question.

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Emergency services also attended and the woman was taken to hospital.

Riley was dismissed from the force in January this year, it is understood.