Apple Inc. (NASDAQ:AAPL) phones have always been a little tough on the pocket book, but not like this. A 13-year-old girl underwent first and second degree burns after her Apple’s iPhone 5C caught on fire inside her pocket, according to a report from the Press Herald.

Apple iPhone 5C fire

The battery of the phone popped up when the girl sat down in the classroom, and later smoke started coming out of it. Her friends told the girl to take off her pants, and asked the boys to leave the classroom. Also, a teacher covered her with a blanket. The girl was admitted to the hospital and released later.

Battery of Apple iPhone exploded

According to one of the fire officials in Kennebunk the battery of the Apple Inc. (NASDAQ:AAPL) iPhone exploded when the girl sat down.

“People should obviously use caution when placing their phones in their back pockets so as not to crush them and cause an electrical short,” one official said.

The principal of the Kennebunk Middle School said that he has never experienced an incident like this before and praised the girl for her “stop, drop, and roll” move.

According to Judy Milligan, mother of the girl, her daughter was given treatment for burns, and she wanted to go back to the school, but the school authorities at Maine told her to take rest for the day. Milligan did not wish her daughter’s name printed in the newspaper.

All batteries prone to fire

According to Andrew Rosenstein, owner of TechPort in Portland, who also repairs Apple Inc. (NASDAQ:AAPL) products, customers buy bad batteries even after knowing the risks. However, the iPhone that caught fire was almost new.

“There’s basically a lithium-ion type rechargeable battery built in (to an iPhone). The battery, as it charges and discharges, it’s really a chemical reaction that can generate heat,” Rosenstein said.

He said that though the incidents like this are very rare, but any battery can burst into into flames in extreme circumstances. Rosenstein said that he uses a fireproof box to keep the batteries away from devices that are under repair to avoid any fire in case of malfunction.

News of phones catching fire while charging have been surfacing for quite some time. Lithium ion batteries are prone to catching fire, and Boeing 787 Dreamliners are a recent example of another problem with lithium ion type batteries.

UPDATE: The phone made a “popping” noise when she sat down, reports USA Today. Fire officials told the paper that they think sitting on the phone caused it to “short out.”