BELLEFONTAINE, Ohio -- Investigators are looking into whether an explosion that leveled a vacant house near Bellefontaine was accidental in intentional.

The house was recently used as a doctor’s office, but had been vacant. Authorities are trying to determine if the explosion was linked to a propane tank on the property, utility service to the structure or was an intentional act.

The explosion, which happened around 10:30 p.m. Wednesday, hurled debris up to a half mile away, knocked over a van and damaged windows of nearby buildings and cars.

The single-family house was last used as an office by Dr. Matthew Hasford, who is a urologist. The office closed in February.

Authorities said medical records were scattered amongst all of the debris. They said it will be a major task to collect all of the paperwork that survived the explosion and put it back in order.