Two young children have died in Mykolaiv, reportedly from carbon monoxide poisoning.

According to the Mykolaiv region police, the children’s bodies were found in an apartment showing no signs of violent death, Ukrinform reports.

“Police officers in Mykolaiv are investigating the circumstances surrounding the deaths of two young children. Preliminary findings indicate that a woman left her four-year-old son and three-year-old daughter alone in the apartment for about half a day. When she returned home in a state of intoxication, she found the children lifeless and the apartment filled with steam,” the report said.

Police received the report from a local resident on October 27. A forensic medical examiner found no external signs of violence on the children’s bodies.

According to preliminary expert conclusions, the children likely died from carbon monoxide poisoning.

Earlier, in Podilsk, Odesa region, three children were hospitalized in serious condition from carbon monoxide poisoning, and a man’s body was found in the same house.