BBCThree people have been found dead and four people taken to hospital after an incident at a care home.
Emergency services were called to Gainsborough Care Home in Ulwell Road in Swanage, Dorset, at 05:20 BST.
Residents have been evacuated from the building to a nearby church hall.
Dorset Police said the deaths were being treated as “unexplained”.
The force added: “The families of those who have died have been informed and the coroner has been notified.
“At this time there is nothing to indicate any risk to the wider public.
“We understand this incident will have a significant impact on the Swanage community and our thoughts are very much with the families of those who have sadly died at this extremely difficult time.”
The home, run by Agincare, has 48 residents, all elderly and some with dementia.
Residents were seen being transferred, some in wheelchairs, to All Saints Church a short distance away.
Emergency beds have also been delivered to the hall.
In a statement Agincare said it has allocated “extra staffing resources” to provide support after an incident at the site, and that residents moved to a village hall and church are “safe and well”.
They said: “We appreciate that this is a stressful and worrying time for those involved, and have allocated extra staffing resources to provide support locally. We are contacting and updating residents’ families.
“We will continue to work with the lead local authority services to return residents into their home at the earliest opportunity, and will provide further updates in due course.”
Gas distribution company SGN said it was called to Gainsborough Care Home earlier on Wednesday.
It said engineers were sent to complete safety checks in the building.
“Our thoughts are with everyone who has been affected by this tragic incident,” a statement said.
BBC reporter on the scene Tristan Pascoe said: “At the moment it’s unclear what exactly happened here, but you can tell from the scale of the emergency services’ response that it’s clearly a serious incident.”
He said he was told by a relative who had visited a resident that “gas or carbon monoxide” was involved.
The local ward member on Dorset Council, Gary Suttle, suggested there was a suspicion the deaths “could be attributable to carbon monoxide, but it has not been proven”.
South West Ambulance NHS Trust said a hazardous area response team environment crew was sent to the scene along with 10 double-crewed ambulances.
Fire crews from across Dorset were sent to the scene. They have been assisted by a crew from Winchester in Hampshire.
Dorset South MP Lloyd Hatton said the deaths at Gainsborough Care Home would “certainly be hitting the whole community hard”.
He told BBC 5Live it was “really important” to give the emergency services space to carry out their inquiries”.
The home received a Good rating when it was last inspected by the Care Quality Commission (CQC) in 2021.
Additional reporting by Emily Ford
