A fire that destroyed a converted Camp Ellis cottage Saturday night is under investigation by officials from the Saco Fire Department as well as the state Fire Marshal’s Office.

A rare winter thunder and lightning storm may have played a role in the blaze at 2 Pineywood Road,  which was unoccupied except for four cats. Their whereabouts are still uncertain, said Lt. Steven Merrill of the Saco Fire Department.

The woman who lived in the house was spending the night at her daughter’s home nearby, Merrill said. A passer-by called in the fire shortly after 11 p.m. Saturday.

“There were weather issues in the area around that time,” said Merrill, who spent Sunday at the scene and will return today.

Merrill said the home is a total loss. After firefighters made their way across icy roads to the site, they were further hampered by waist-deep snow around the house and fire hydrants that had not been shoveled out.