Man, 18, stabbed in the chest in attack in Bournemouth's Lower Gardens

Detectives have now launched an investigation and are appealing for witnesses or anyone with information to come forward.

Dorset Police received a report that at around 11.50pm last night an 18-year-old man had sustained a stab wound to the chest after being assaulted in the Lower Gardens in the town centre.

The victim had been walking in the gardens toward Bournemouth Pier with two friends when they walked past a man and a woman who were sitting on a bench.

As they walked past, the man began shouting and got up and assaulted the victim before he and the woman made off in the direction of Bournemouth Square.

Police and the ambulance service attended and the victim was taken to hospital, where he remains in a critical condition.

The offender is described as wearing all black clothing with a black hat and a mask. The woman he was with is described as white, short and chubby.

Detective Inspector Shaun Inkpen, of Bournemouth CID, said: "This appears to be an unprovoked attack that has left the victim with serious injuries and we have launched a full investigation to identify the person or persons responsible.

"We are carrying out a number of enquiries and I would urge any witnesses or anyone with information that might assist our investigation to please come forward.

"There will be an increased police presence in the area as we carry out further enquiries and a cordon remains in place at the scene. Officers can be approached by members of the public with any concerns."

Information to Dorset Police on 101, quoting occurrence number 55210091147, or the free and anonymous Crimestoppers line on 0800 555 111.