A 60-year-old woman has been arrested on suspicion of manslaughter after three people died at a care home in Swanage.
Dorset Police said they received a report at 7.16am on Wednesday regarding three residents who were found dead at the Gainsborough Care Home in Ulwell Road.
Seven people were taken to hospital as a precaution and other residents of the address were evacuated to a location where they can receive appropriate care.
Police said the deaths are “currently being treated as unexplained”, adding that detectives have confirmed “possible carbon monoxide poisoning is the primary line of inquiry”.
Dorset Police said a 60-year-old local woman was arrested on suspicion of manslaughter on Wednesday evening and remains in police custody.
Detective Chief Inspector Neil Third, of the major crime investigation team, said: “As part of our investigation, we have made one arrest to enable us to establish whether there have been actions or omissions which are grossly negligent and gather as much information as we can about what has happened.”