Two students were wounded by a fellow student who died in a shooting in a hallway at Great Mills High School in southern Maryland on Tuesday morning, according to the St. Mary County sheriff’s.

A school resource officer shot the student gunman, who fired back with a handgun, Sheriff Tim Cameron said. The school resource officer was not injured, Cameron said.

"He pursued the shooter and engaged the shooter," Cameron said of the school resource officer, whose identity has not been released.

The two students who were injured — a 14-year-old boy and a 16-year-old girl — were being treated at local hospitals, officials said. Neither their identities, nor the shooter’s, were released.

The boy is in good condition and is being treated at MedStar St. Mary’s Hospital. The girl was initially brought to MedStar  but was later stabilized and transferred to University of Maryland Prince George’s Hospital Center.

The shooting happened just before 8 a.m. at the school, county spokesman Tony Jones said from the emergency operations center.

``This is what we train for. This is what we prepare for and this is what we pray we never have to do," Cameron said. "And on this day we realized our worst nightmare that our greatest asset -- our children -- were attacked in a bastion of safety and security, one of our schools."