A robber, who was part of a gang who carried out a 'professional and planned' raid on Great Yarmouth jewellers, escaping with valuables worth more than £5000, has been jailed for three years.

Andrew Ball, 23, carried out the robbery with two others, at the shop in Victoria Arcade, in which the owner was punched to the ground and threatened with a stungun device, Norwich Crown Court heard.

Charles Kellett, prosecuting, said the other two robbers were involved in the violence towards the shopkeeper, and then Ball rushed into the shop and grabbed chains and charms from a display cabinet, which were valued between £5000 and £6000.

He said the three men then made their escape, but Ball was caught nearby, although the property was never recovered.

He said the jewellery shop owner was not insured for the loss of the 30 chains and 40 charms which were taken in the 'smash and grab' raid.

Mr Kellett said the owner suffered bruising in the raid and said the two other robbers have never been caught.

Ball, of North Denes Road, Great Yarmouth, admitted robbery on August 5, this year.

Stephen Dyble, for Ball, said although he took part in the raid, he was unaware that force was going to be used against the shopkeeper.

He had only entered the store after the other two men had overpowered the shopkeeper and said that Ball played a lesser role in the robbery.

Mr Dyble said that Ball pleaded guilty at the earliest opportunity.

Jailing him, Judge Anthony Bate said it had been a 'professional and planned' raid on the jewellers.

He said the two others involved in the raid had distracted the shopkeeper using force, and accepted that Ball did not know they had a weapon on them: 'What you did was to snatch the goods from the broken case and then make off with the jewellery. You were apprehended close to the scene.'

He said Ball deserved credit for his plea.