India says 11 of its citizens died in the incident in the Caucasus country, which remains under investigation.

Twelve people have died from suspected carbon monoxide poisoning in Georgia, authorities in the Caucasus country say.

The incident took place at a ski resort in Gudauri in the north, Georgian police said on Monday.

The bodies of 11 foreigners and one Georgian national were discovered on Saturday in a sleeping area above an Indian restaurant at the resort, police confirmed.

“Preliminary tests do not indicate any trace of violence on the bodies,” the Ministry of Internal Affairs said in a statement. “A power generator was placed in an indoor area [and] turned on, probably after the power supply was turned off.”

The statement added that forensic experts are gathering evidence related to the case. They are trying to determine if their deaths amount to “negligent manslaughter”.

The Internal Affairs Ministry statement said the victims were believed to be employees of the restaurant.

Although their identities have not been released, the Indian embassy in Georgia said on Monday that 11 of the victims were Indian citizens.

“The Embassy of India in Tbilisi is saddened to learn of the unfortunate passing of eleven Indian nationals in Gudauri, Georgia, and extends its deepest condolences to their families,” it said.

“The Embassy is working closely with local authorities to facilitate the prompt repatriation of the mortal remains to India. We are also in contact with the bereaved families and are committed to providing all possible support.”

Known as a “silent killer”, carbon monoxide is an odourless gas produced when fossil fuels don’t burn fully. If inhaled, it can prevent oxygen from being carried by the blood around the body.

According to the Centers for Disease Control and Prevention in the United States, symptoms of carbon monoxide poisoning include headache, dizziness, weakness, vomiting, chest pain and confusion. But people who are sleeping can die of it without experiencing symptoms.

Gudauri is a popular tourist destination for skiers and snowboarders. The resort has not yet publicly commented on the deaths.

Georgia is a former Soviet republic whose western area lies on the Black Sea and whose north is nestled in the Caucasus mountains.