A 12-year-old boy who was playing yesterday with a fireworks shell found on a field next to a Baltimore County elementary school suffered burns to his cheek and hand when the device detonated near his face, police said.

Darren A. Moscerella, of the 100 block of Lyndale Ave. in Fullerton, was in fair condition yesterday at Johns Hopkins Children's Center, a hospital spokeswoman said.

The incident occurred about 2 p.m., police said. Someone called 911 to report a loud explosion and a group of children running in the field at 4400 Fullerton Ave.

Authorities said they are investigating whether the child found unexploded fireworks left over from a county-sponsored professional display held the night before next to Fullerton Elementary School.