A THUG who fractured a man’s jaw amid claims he hit his sister with a hammer has been jailed for 16 months.

William Gibson, 60, pounced on Alan Monaghan, 54, at The Black Bull pub in Glasgow city centre's High Street on August 10 2019.

Gibson struck Mr Monaghan through a set of doors and punched him on the back of the head.

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He later remarked: “I had to get him, he hit my sister with a hammer and got away with it.”

Gibson pleaded guilty at Glasgow Sheriff Court to the assault to Mr Monaghan’s severe injury.

The court heard Mr Monaghan was in the pub by himself drinking a can of cola before leaving at midnight.

Gibson followed him and approached him from behind.

Prosecutor John Bedford said: “Mr Monaghan felt a strike on the back of his head, fell between two doors and felt a punch.”

Gibson said: “You b****** that’s for my Lizzie.”

He was hauled away from the bleeding Mr Monaghan by a woman before making the hammer comment.

Mr Monaghan suffered an acute jaw fracture, multiple nasal bone fractures and two broken teeth.

He told police officers that he had been in a relationship with Gibson's sister but it ended.

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Gibson, of the city's Germiston, was later traced and arrested.

Sheriff Paul Crozier said: "You took drink, followed him and committed a vicious attack from behind.

"When he fell to the floor, you continued your alcohol fuelled attack.

"There was no provocation and this was revenge as far as you were concerned.

"This is clear in what you said to him about Lizzie and the injuries sustained were severe."