Screenshot by Chris Matyszczyk/CNET

It's not something you can ever expect.

It was 7:40 a.m. in the Middle School of the Kennebunks in Maine. A teen girl sat down in her classroom.

Then she heard a pop emanating from her back pocket. As Seacoast Online reports, before she knew it, her back pocket appeared to be on fire. She then reportedly fell to the ground, rolled, and tried to get out of her pants.

A teacher grabbed a blanket and fellow students tried to help.

The culprit is said to have been her iPhone. Images suggest it had caught fire.

The school principal, Jeff Rodman, told Seacoast Online: "It was something that I don't think people had ever seen before. I've never seen anything like that."

The teen was taken to the hospital, where she was treated for burns and later released.

The division chief of the local emergency medical services, Andrew Palmeri, told Seacoast Online that the phone's battery had "shorted out." He suggested that the phone had been crushed in the teen's back pocket. Local fire services are investigating.

I have contacted Apple to see whether the company has any comment about the incident and will update, should I hear back.

Cell phones of whatever brand do catch fire. iPhones have caught fire on planes, just as Droids have exploded in ears.

The relief in this case is that the teen doesn't seem to have been seriously hurt.