UK police have released CCTV showing the shocking moment a man punched another man so hard he ended up in coma for 10 days with a fractured skull.

The footage shows the moment Andrew Mason was knocked unconscious in Fever nightclub by Maxwell Banbury in Devon, England in March this year.

It begins with Banbury sitting at a table having a drink and the victim dances with a girl, reportedly Banbury's girlfriend.

View photos Banbury is seen on the CCTV sitting at the table. Photo: Devon and Cornwall Police More

Banbury walks up to him and then punches him in the head so hard Mr Mason immediately drops to the floor unconscious.

Banbury returns to his table to finish his drink before quickly leaving the nightclub, the victim is still out cold on the floor before staff realise what is going on and rush to his aid.

View photos Banbury reportedly saw the Andrew Mason trying to dance with his girlfriend before the attack. Photo: Devon and Cornwall Police More

DC Phil Lawes, investigating officer in the case, said: "This was a totally unprovoked assault with no justification whatsoever.

"The severity of this assault shockingly illustrates how a single punch can cause very serious injuries – and the consequences of this attack could have been much worse.

View photos Banbury is seen viciously punching the Mr Mason on the CCTV. Photo: Devon and Cornwall Police More

"Devon and Cornwall Police will investigate these types of assaults robustly and bring the offenders to justice," reports the North Devon Journal.

Banbury, 19, of Chantry Avenue, Bideford, admitted grievous bodily harm and was jailed for 16 months, suspended for two years.

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