Four people were being questioned today about the murder of a lodger found dead at the house where he was staying in Co Down.
Two men, aged 40 and 50, and an 18-year-old woman were arrested late last night, while a man detained yesterday remains in custody.
Police today named the victim as Edward Kelly (58) of Central Avenue, Bangor.
His body was discovered on Thursday night in the coastal town property where he had been renting a room.
Mr Kelly's death was one of two within hours of each other that were being treated as separate murder inquiries by the PSNI.
Both Mr Kelly and 75-year-old Annie McCartan, whose body was discovered in the bathroom of her home in Warrenpoint, Co Down, had suffered head injuries.
Mrs McCartan had been violently attacked, detectives said. She was found dead when her two sons called at the house in the town's Summer Hill area on Thursday.
The last person to see the woman alive, four hours earlier, was her daughter-in-law. Detectives have appealed for anyone in the Summer Hill area who noticed anything unusual between 4pm and 8pm to make contact.