Police vans could this morning be seen blocking entry to both ends of Paradise Lane, next to The Deck of Cards, while forensic investigations were carried out.

Detectives are also appealing for witnesses to the assault, which happened at about 2.45am today. The 31-year-old victim was found unconscious with severe head injuries by police officers called to the area.

He was taken to Queen Elizabeth Hospital where he is being cared for in the intensive care unit.

Three men were arrested nearby on suspicion of causing grievous bodily harm and are currently being questioned. They are a 26-year-old from Mansfield, a 49-year-old from St Neots and a 28-year-old from Sheffield.

The victim, who comes from the Leiston area of Suffolk, is believed to have spent part of the evening in the Chicago Rock Cafe in Norfolk Street before visiting a nearby take-away.

Anyone with information about the assault or any related incidents is asked to contact Detective Chief Inspector Neil Firm, at Lynn CID, 0845 456 4567.