A knife-point robber unlawfully at large from prison landed a 'rain of blows' in an unprovoked attack on a 63-year-old celebrating his granddaughter's 18th birthday.

Paul Smith was on day release from prison while serving an 11-year sentence for aggravated robbery on October 7, 2017.

He was due back at 4pm but at 8.50pm he walked into the White Horse in King's Lynn.

Norwich Crown Court was shown CCTV of Smith, 53, walking into the pub before heading straight towards his victim who was sitting with his family.

He landed a "volley of punches" which knocked out his victim's front teeth and left him with two black eyes and facial injuries.

Smith admitted causing assault occasioning actual bodily harm.

Sentencing him, Judge Stephen Holt said there had been an "unconscionable delay" of two years bringing the case to court.

"The police knew your name that night and the incident was all on CCTV," he said. "For some reason nobody can understand, other than pressure on the police, they did not start investigating this properly for months.

"That is unfair to you and deeply unfair to the victims.

"This is happening more and more in crown courts where people are released pending investigation and the case disappears into the long grass.

"It ends up with injustice."

The court was told the attack was broken up by other drinkers in the pub, and Smith returned to prison that night.

"Because of the incident being so random [the victim] worries something like that will happen again," said Martin Ivory, prosecuting.

"His main concern is his granddaughter won't get over the incident. She keeps reliving it over and over again."

The court heard Smith has 53 convictions for 163 offences.

They include dishonesty, possession of weapons offences and a robbery in 1999 for which he received six years in prison.

In 2013 he was jailed for 11 years for an aggravated burglary - a knife point robbery of a lone woman in her home.

David Stewart, mitigating, said Smith had spent the day drinking with some women and an "allegation" was made against the victim.

"It seems he, in a totally misguided sense of chivalry, went for the complainant," said Mr Stewart.

He added Smith "wishes to convey his remorse".

Judge Stephen Holt told Smith: "Within seconds you started landing a rain of punches and blows to his head and his face. It was a completely unprovoked attack in front of his family."

Smith, of HMP Elmley, was jailed for 12 months.