COLUMBUS, Ohio (AP) — Authorities are investigating what they call a suspicious fire that broke out at a central Ohio home where two women and an 11-year-old boy were stabbed to death before their remains were placed in a tree.

Eastern Knox County Joint Fire District Chief Larry Stimpert says firefighters were sent Monday night to the Howard home of Tina Herrmann, where they found the porch on fire.

Stimpert says the fire was quickly contained. He says it burned the porch and melted some siding but didn't extend inside the home.

The cause of the fire is being investigated. No one was home at the time.

Visitation services are being held Tuesday for Herrmann and the other two victims killed at the home. Their remains were found last week in a hollow tree trunk in a wildlife preserve about 20 miles away.