MORRISVILLE, Pa. - Police in suburban Philadelphia say a fire at a motel might have been started to destroy evidence from a sexual assault.

It happened at the Country House Motel in Falls Township.

When the fire trucks pulled into the parking lot, it looked like an ordinary fire call, reported Fox 29's John Atwater.

According to the fire marshall, the fire started in one unit but quickly spread to others.

But just as firefighters were dousing the flames, the investigation took a turn.

"About an half-hour later, we got a phone call from a female at one of the 7-Eleven stores on West Trenton Avenue who had claimed to be sexually assaulted," says Lt. Ron MacPherson of Falls Township Police.

A woman in her early 20s told Falls Township police that a man she met through a mutual friend drove her from Trenton, N.J., to the motel in Morrisville, Pa., and forced her into a room at gunpoint.

The woman reported that the man sexually assaulted her in the room several times but she eventually managed to escape through a bathroom window.

"She claims to become ill and at that point goes into the bathroom and she escapes through one of the bathroom windows," says Lt. MacPherson.

They think she had escaped from a man who police say was seen at another 7-Eleven two hours earlier. Surveillance video was rolling as police say he bought a condom and a hot dog. The woman was waiting in the Pontiac outside.

A fire was started in the room where the woman reported the assault and police believe the man started the fire to cover up the crime.

It's all but wiped out business at the Country House Motel. But the owner will not be able to rebuild until police construct their case against a man who they say is violent and unpredictable.

No one was hurt in the fire.

Police have released photos from the convenience store's surveillance camera of a man identified as a person of interest.

The victim was treated at a hospital and is expected to be fine.