A murder investigation has been launched after a man died in Bishop Auckland yesterday evening (November 29).
The 41-year-old man, who has not been named, was found by emergency services unresponsive outside a property in West Lane.
Despite receiving medical attention he was pronounced dead at the scene.
Police have arrested three men and one woman, all in their 40s, in connection with the incident.
All of them remain in custody.
There has been a strong police presence at the scene all day as enquiries are still ongoing.
A Bishop Auckland police spokesperson said: "A murder investigation has been launched following the death of a man outside an address in Bishop Auckland, yesterday evening (Wednesday, November 29).
"Emergency services attended West Lane at around 6pm and found a 41-year-old man unresponsive.
"Sadly, despite medical treatment, he was pronounced dead at the scene.
"Three men and one woman, all in their 40s, have been arrested in connection with the incident and remain in police custody.
"Enquiries are ongoing to determine the circumstances of the death.
"A police presence will remain at several addresses in the town while enquiries are carried out.
"Detectives would like to reassure the public that there is not believed to be any wider risk to the community.
"Anyone with any information is asked to contact Durham Constabulary on 101, quoting incident reference number 351 of November 29."
The air ambulance confirmed that they were called to the scene just before 6.30pm.
A spokesperson said: "Yesterday our critical care team was activated at 6.28pm to reports of an assault in Bishop Auckland.
"We had two doctors and paramedic respond on a rapid response vehicle and they arrived on scene at 6.48pm."
Residents of West Lane have been left shocked by the awful incident.
One resident, who wished to remain anonymous, said: "There were so many police cars here last night.
"People are saying that there were men fighting with knives on the green.
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Another, who also wished to remain anonymous, said: "I heard a commotion and angry voices but I just thought it might be some angry young people.
"Now we know what happened I worry they might have been involved."