A 48-year-old man was under police guard in hospital today after being arrested on suspicion of knifing to death a man during a fight in a seaside town.
A violent confrontation between men in a flat in Ceylon Place, Eastbourne, East Sussex, spilled out into the street at around 9pm last night.
Witnesses saw paramedics frantically try to revive an injured man on the pavement but the 39-year-old died a short time later from his injuries.
A man arrested on suspicion of murder was also injured during the incident and was under guard at Eastbourne District General Hospital.
The victim, who has not been named, and the arrested man are believed to have known each other but neither is understood to have been living at the property.
Detectives said they were not looking for anyone else in connection with the killing. A weapon understood to have been used in the attack has been recovered.
Detective Chief Inspector Nick May, from Sussex Police's major crime branch, said they were struggling to confirm the identity of the dead man and efforts were being made to trace his next of kin.
He added that it was too early to suggest a motive for the killing, and that forensic and house-to-house inquiries continued in the road, close to Eastbourne town centre.
Mr May said: "The main incident was contained in the flat and the man did then end up on the pavement in front of the address where paramedics struggled to save him without success."
The arrested man sustained non life-threatening injuries which were not knife wounds, he added.
A post-mortem examination will be carried out later on the man who died.
Neighbour Mamadu Bakde, 32, saw paramedics try to resuscitate the dying man. He said: "He was lying on the pavement and paramedics were trying to resuscitate him.
"There was another man who was injured. He had facial injuries.
"There was a lot of police and ambulances here last night but I didn't hear any shouting or anything because I have double glazed windows.
"It is very concerning."
Some residents in the road said it had a problem with drugs and alcoholics but detectives denied suggestions the flat was a half-way house for addicts.
One neighbour, who declined to be named, said: "This isn't a safe area. I have had two drug addicts climb over my wall and I live in fear of being attacked.
"The heart is going out of the place."
Another resident, Janette Calverley, 46, who lives further down from the crime scene, said: "There are a lot of houses of multiple occupancy in this road.
"But mainly, as far as I'm aware, they are lived in by long-term tenants and normally we are quite a happy street."
Blue tarpaulin covered the basement area of the three-storey building today as police officers checked bins, gardens and pavements as part of their investigation.
Speaking at the scene, Eastbourne Lib Dem MP Stephen Lloyd said: "Thankfully these sort of appalling crimes are extremely rare in Eastbourne and I'm sure the police are doing everything necessary to complete their inquiries."
Anyone with information is asked to call Sussex Police on 0845 6070 999, quoting Operation Govan.