9-year-old girl suffers 'life-altering' injuries after illegal explosive detonates in her hands: Police

A 9-year-old girl is in critical condition with "devastating" and "life-altering" injuries after an explosive her dad bought detonated in her hands, according to Philadelphia police.

The girl was home without her parents Sunday morning when she picked up the device and it exploded, Philadelphia Police Capt. Mark Burgmann said at a news conference Monday.

"It was like a loud boom -- it was so loud, I heard it in the back room," neighbor Judith Sierra told ABC Philadelphia station WPVI. "There was smoke coming out of the house."

The little girl suffered severe injuries to both hands, cuts and burns to her chest and face as well as burns to her eyes, Burgmann said.

Philadelphia police bomb squad detective Tim Brooks classified the explosive as an "illegal explosive device" -- not a firework -- because these devices are not legal to buy.

"There's no quality control" in the U.S. with these devices, he said, so what's inside is unclear; just holding and shaking it can cause an explosion.

It's not clear if the 9-year-old lit the device or if it went off while she was handling it, he said, adding that "these are inherently dangerous just by their possession."

"It shouldn't have been in her hands to begin with," Burgmann said.

This device was one of two illegal fireworks the 9-year-old's father bought from an unknown individual on Saturday, Burgmann said, and police are trying to determine who the seller is.

The girl's family is "devastated" and is cooperating, Burgmann said. Charges are possible, he said.