A murder investigation has been launched after two women were found dead at a house early today, police said.
Officers were called to Thame, Oxfordshire, at 2.21am where the pair were found with fatal injuries, Thames Valley Police said.
A third woman was taken to hospital but her condition is not thought to be life-threatening, a police spokesman said.
A man was arrested on suspicion of murder in Thame Market Place shortly afterwards and he was being questioned at Abingdon police station.
The police spokesman said: "Nobody else is being sought for questioning at this time."
The ages of the victims have not been released.
Police and forensic investigators were at the scene this morning as neighbours spoke of their shock at having a murder inquiry in their "delightful" town.
One resident, who declined to be named, said: "All the police have told us is that it's a major incident. Neighbours are saying it is a domestic.
"I don't know the people involved but Thame is a delightful town. It is a shock that something like this has happened here.
"I have lived here for 12 years and this is the first time that I have had a major incident in my street. I heard a helicopter flying overheard but I presumed there had been a car accident.
"It had its searchlight on and, thinking about it now, they must have been looking for someone. People haven't been allowed to take their cars out and that's all I know."
Another neighbour, who also refused to be named, said: "There have been police here standing about but I'm keeping well out of it.
"It's a very nice area and we have had no trouble in the time we have been living here."
A South Central Ambulance Service spokeswoman said an officer and two ambulances were sent to the scene but she directed all further inquiries to police.