The Securicor worker was filling an ATM at Nationwide Building Society in Main Road, Duston, Northampton, at 0115 BST on Saturday, when he was attacked.

The gang stole the cash he was carrying and ran off towards Meeting Lane.

Two white men aged about 21 led the attack. One had a medium build and light-coloured hair. The second was slim with light-coloured, short hair.

The woman was white with black, shoulder-length hair, about 5ft 7in tall and was wearing a dark, knee-length coat and jeans.

The fourth person was a white man, about 25 years old, 6ft 2in tall, slim and looked tanned.

He had a bald head and was wearing dark trousers, a light coloured shirt and very distinctive bright red shoes with white stitching.