Harrowing footage has emerged of the man who stabbed 11 people on board a train heading for London.

Security cameras captured the moment he scaled the station’s fence and crossed its carpark, dressed in black and wielding what witnesses described as a huge kitchen knife.

Eight minutes after the first panicked phone call to emergency services, armed police had the man surrounded and tasered him.

One passenger told British media they thought it was a Halloween prank, until they realised the blood on their hands was real.

Of the 11 victims, one is fighting life threatening injuries in hospital.

He’s the train’s conductor who’s been praised by police as a hero for shielding passengers.

They’ve also hailed the quick thinking of the train driver, Andrew Johnson – a veteran of the Iraq war – for immediately diverting the service to Huntingdon.

The British government knows it needs to crack down on stabbings and it’s recently set a target of halving knife crime within a decade.

The latest data shows nearly 60,000 knives have been taken off the streets of the UK since last July.

Confidence in the success of the scheme has now been shattered in one night.

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