The victim was approached by an unknown man in Commercial Road around 9.20pm who shouted at him before punching him several times in the face.
Minutes later, three boys then approached the man, with one of them also assaulting him.
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The victim, a man in his 50s, was knocked unconscious and taken to hospital for treatment.
‘It is believed a number of people witnessed the incidents and we are keen to speak with them,’ a police statement said.
‘The man is described as being between 30 and 40 years old, Asian, with a beard and wearing a blue denim coat over a light jumper and blue jeans.
‘The boy is described as being around 17 years old, white, of muscular build, wearing grey shorts and a hooded top.’
Anyone with information should call 101, quoting the reference 44210153356.
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