A police officer who was caught on camera telling a young woman: 'I will knock you clean f***ing out' has kept his job.

PC Boulton was filmed threatening Nikki Wright, who is just five feet tall, as he patrolled Hanley town centre in Stoke-on-Trent in the early hours of the morning - but escaped with just a written warning.

In the clip, as he approaches a group of revellers, the Staffordshire Police officer shouts at the petite 22-year-old: 'Do that to me again and I will knock you clean f***ing out.'

The video then shows him threaten Miss Wright again after her shocked boyfriend Andrew Smith, also 22, asks him to repeat what he said.

After being challenged, he says: 'You heard, I said I will knock her out.'

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PC Boulton was suspended after he was filmed telling a young woman: 'I will knock you clean f***ing out' but has returned to his duties after escaping with just a written warning

Nikki Wright, 22, was threatened by the police officer after a night out in Hanley, Stoke-on-Trent in July

Mr Smith then asks a second time: 'You said you'd knock her out?'

PC Boulton is then clearly heard to say: 'Yeah, yeah. If she tries to throw a punch at me, of course I would.'

Mr Smith recorded his collar number - 4595 - and posted the video on Facebook where it was viewed by more than 800 people.

Staffordshire Police suspended the officer from his duties after the row erupted outside a bar on Trinity Street on July 20 this year.

But now, PC Boulton has been allowed to return to work after he was handed a written warning.

His duties will also be supervised after Staffordshire Police carried out an investigation into the incident.

The force found he used threatening language towards Miss Wright but threw out two complaints which included two allegations of assault and one that the officer lied.

Chief Superintendent Martin Evans, of Staffordshire Police, said: 'The comments made by PC Boulton were not acceptable and below the standards expected of an officer.

'We concluded that the circumstances of the upheld complaint did not constitute grounds for dismissal and were suitable to be dealt with via a misconduct meeting.

Miss Wright and her boyfriend Andy Smith, 22, who filmed the police officer during a night out

'This meeting resulted in PC Boulton receiving a formal written warning. He has returned to work and his conduct will be closely monitored by supervision.

'We expect our officers to provide the highest standards of professionalism at all times. If an officer's behaviour falls below the standards expected we would encourage it be reported so we can scrupulously investigate.'

Staffordshire Police and Crime Panel member, Joy Garner, also backed the decision, calling the ruling the 'right result'.

She added: 'We don't know what the officer had been doing leading up to the event.

'It's right and proper that he's been dealt with because speaking to the public in that way is wrong.

All I asked for was a hand written letter of apology but instead I got a photocopied printed letter through the post making excuses Nikki Wright

'It's so unusual for one of our officers to behave in this way - I hope a line can be drawn under it all.'

Today, Miss Wright blasted the decision to let PC Boulton off with 'a slap on the wrist'

She said: 'All I asked for was a hand written letter of apology but instead I got a photocopied printed letter through the post making excuses.

'He basically got off with a slap on the wrist.

'The letter, which I got in October, said: "I regret the words I said to you and these are very much out of character and in the heat of the moment.

''I can only apologise for the words I used, they are clearly not what is expected of a police officer, but we are all still human and after a particularly stressful 11-hour shift this reaction was very much human.

''Once again I apologise for the words I used, I hope that you accept this.''

Speaking after the incident, she had said she was 'terrified' when the officer verbally abused her.

She added: 'I am just a little lass and was genuinely terrified I was going to be hurt when this big officer came and threatened me.

'You can hear in the video how panicked I am and that I'm close to tears.

'I was trying to help my friend who had collapsed and was shouting for an ambulance when this officer approached me and said what he said.

The incident took place in Trinity Street, Hanley, Stoke -on-Trent (pictured), just after 2am in July this year

'If it had been the other way around and I had said that to him then I think I would have been arrested.

'I was so shocked. I have never been in trouble with the police before and I'm a law abiding person. How can a police officer be allowed to get away with this?'

Nikki's boyfriend Andrew Smith, 22, added: 'It was all very chaotic but the officer was very rude and aggressive.