Two police officers are being investigated for potential gross misconduct over alleged failures to properly investigate an attack potentially linked to the Huntingdon train stabbings.
Ricky Butcher said he was outside Fletton Club in Peterborough waiting for a taxi with a group of people when he was stabbed by a man on 27 September.
He previously told the BBC he required stitches for a cut to the mouth and his face is "numb, and probably always will be, due to the cut".
Mr Butcher said he was "fuming" that Cambridgeshire Police stopped their investigation two days later.
"They could have taken it more seriously - I had five witnesses with me," he said.
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Cambridgeshire Police said in November that it had commissioned an internal review of events, including Mr Butcher's case, prior to a mass stabbing on an LNER train service from Doncaster to King's Cross on 1 November.
Anthony Williams, 32, is charged with 10 counts of attempted murder over the Huntingdon incident.
An IOPC spokesperson said on Thursday: "Our independent investigation into the police complaint from a man who was injured during a reported assault incident in Fletton, Peterborough on 27 September 2025 is progressing.
"The complaint relates to Cambridgeshire Constabulary's investigation into the incident at the time.
"In January, we notified two Cambridgeshire police constables that they are being investigated for potential gross misconduct, which relates to alleged failures to properly investigate the incident.
"This does not mean that disciplinary proceedings will necessarily follow.
"At the end of our investigation, we'll decide whether any officers should face disciplinary proceedings.
"Our investigation began following a referral from the force in November 2025."
(c) Sky News 2026: Probe into police response to attack linked to Huntingdon train stabbings
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