Authorities have charged the mother of twin 2-year-old boys who were killed in a fire this year at their western New York home.

The Genesee (JEN'-uh-see) County Sheriff's Office says 25-year-old Heather Ace was arrested on child endangerment charges Wednesday, four months after a fire broke out at her Batavia (bah-TAY'-vee-ah) home.

Officials believe the May 20 blaze began inside or near her twin toddlers' bedroom. Police say Ace had left the boys home alone for about an hour and a half.

Michael and Micah Gard were found in their bedroom on the first floor of the home. Authorities have said they died of smoke inhalation.

The cause of the fire remains under investigation.

Ace is expected in court next month. It wasn't immediately known if she has an attorney.