Authorities say two girls and their mother were dead before a house explosion and fire killed their father and shook homes throughout the neighborhood — (USNews.com)

The girls were either strangled or smothered, the Summit County’s medical examiner said. Their mother died of a Prozac overdose, officials said, and their father, 43-year-old Jeffrey Mather, died of burns after he set the fire using gasoline.

His death has been ruled a suicide.

All four bodies were found Jan. 11 inside the Northfield Center Township home. Mather’s wife and daughters were discovered in a first-floor hallway. Investigators suspect they had actually been upstairs and fell to the first floor when the ceiling collapsed.

It’s unclear if 43-year-old Cynthia Mather killed herself or was poisoned, a medical examiner’s investigator said, but she did have a prescription for the antidepressant. The medical examiner said it couldn’t be determined who had killed 8-year-old Ruthie and 12-year-old Alyson.

“It is unclear which parent is responsible for the death of the two children or how the children were asphyxiated and we will not speculate on the circumstances,” the medical examiner said in a news release.

Jeffrey Mather, who according to media reports was a deacon at his church, said he had been suffering from severe depression and wanted to end it all, according to a police report.

In early December, he heard a “dark voice” encouraging him to kill himself in a park, according to police, and had been seeing a counselor since then.

An officer with the Cleveland Metroparks had found Mather alone with a shotgun loaded with a single slug. Mather told the officer he had put the shotgun to his head several times but put it down because he saw park visitors walking nearby, the police report said.

Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.