Police have launched an investigation into the death of a man after he was bitten by a dog.

West Yorkshire Police said officers received calls from 1.36pm on Saturday reporting an altercation a short time earlier on the old train line footpath off Blacker Lane in the Calder Grove area of Wakefield.

A 55-year-old man was taken to hospital in a critical condition and died shortly after 7pm last night.

The force arrested a 55-year-old man on suspicion of murder and being the owner of a dog dangerously out of control in a public place causing injury, who is currently in custody.

A dog, understood to have been involved in the incident, was seized by police.

Detectives are appealing for any witnesses to come forward, particularly two people who stopped to assist the injured man.

These people, one of whom was called Sophie, helped direct officers during the incident which took place in an area used by walkers.

Detective chief inspector Michael Cox, of the Homicide and Major Enquiry Team, said: “Sadly, a man has died and it is really important that we understand the circumstances of what has taken place.

“We know that two people, one named Sophie, stopped to assist the injured man and direct officers. We would urge these two women to come forward to help us with our ongoing enquiries into this tragic incident.

“The initial altercation has happened in an area used by walkers and we are urging anyone who has potentially seen or heard any part of the exchange between these two men to please make contact.”

Police encouraged anyone with further information to contact the Homicide and Major Enquiry Team or call 101, quoting crime reference 13260465524.

Information can also be passed to independent charity Crimestoppers anonymously via 0800 555 111 or online.