The victim was standing by his van in Landsdowne Road, at around 7.30pm on Tuesday January 29th, when the men approached him, demanding the van keys and his wallet.
The delivery man told them to go away, but as he turned back to the van they slammed the vehicle's door on his arm causing serious injuries. Nothing was taken during the incident.
The first man is described as:
White, aged 16-20, 5'9", slim and wearing blue jeans, a plain hooded top and a baseball cap. He spoke with a foreign accent.
The second man is described as:
White, aged 16-20, 5'3", slim and wearing blue jeans and a blue padded jacket with trainers.
The third man is described as:
White, aged 16-20, five foot, slim and wearing a dark grey hooded top and black tracksuit bottoms.
PC Lucy Bright said: "I would like to hear from anyone who has any information about this robbery, particularly any witnesses who may have seen the incident at the van."
Anyone with information should contact PC Bright on 101
POLICE 101, Emergency 999, Crimestoppers 0800 555 111 & NEWSDESK 01733 345581 E&OE