A man walked into his father's workplace and broke his jaw, leaving him needing surgery to repair it.

Graham Orrock Jr, who previously served a six-year jail term for attacking a pensioner with his own walking stick, walked into the Don and Low textile factory in Forfar, Angus, on August 19.

He demanded his father Graham Orrock Sr top up his electric meter but was instead asked to leave.

Minutes later Orrock Jr returned and began "bawling and shouting" in his father's face.

He was jailed for two years and eight months at Dundee Sheriff Court on Friday.

Fiscal depute Eilidh Robertson said Mr Orrock Sr had been left with a plate in his jaw and on a liquid diet for six weeks as a result of the attack.

She said: "The accused then punched the complainer four times on the face. One of the complainer's colleagues told the police that the punches were 'really hard'.

"Another employee stepped in and separated the accused from his father.

"The accused was asked once more by his father to leave the locus and this time he agreed."

She added: "The complainer called the police. He went to Ninewells Hospital where he was diagnosed with a broken jaw.

"He was admitted and he underwent surgery under general anaesthetic the following day, during which a metal plate was fixed into his jaw. The plate will remain in place permanently.

"He was advised to follow a liquid diet for six weeks following the surgery.

"The complainer attended a follow-up appointment around a week after the surgery and it was noted that he was still sore and slightly swollen, but that the wound was healing well."

Orrock Jr, 29, a prisoner at HMP Perth, pleaded guilty on indictment to a charge of assault to severe injury committed on August 19.

Defence solicitor Grant Bruce said: "He's under no illusions and he knows the only disposal is a custodial sentence. He accepts he has no defence to this matter and no excuses either.

"He and his father have had a turbulent relationship but he did not set out that day to hurt his father. He was shocked by his own actions."

Sheriff Alastair Brown jailed Orrock for two years and eight months.

He said: "That would have been four years but for your early guilty plea."