March 20 (UPI) -- A student opened fire at a Maryland high school Tuesday morning, leaving two students injured and the gunman dead, local law enforcement said.
The perpetrator, 17-year-old Austin Wyatt Rollins, shot a girl and a boy at Great Mills High School in St. Mary's County, Md. -- about 55 miles southeast of Washington, D.C.
Officials said Rollins died following an exchange of gunfire with a school resource officer.
St. Mary's County Sheriff Tim Cameron said law enforcement believe Rollins had a "prior relationship" with the female victim, though it's unclear if that was part of the motive.
"You train to respond to this and you hope that you never ever have to," Cameron said. "This is the realization of your worst nightmare -- that, in a school, that our children could be attacked. And so as quickly ... as that school resource officer responded and engaged, there's grievous injuries to two students."
"We are closely monitoring the situation at Great Mills High School," Maryland Gov. Larry Hogan said on Twitter, adding that state police were "in touch with local law enforcement and ready to provide support. Our prayers are with students, school personnel, and first responders."
Great Mills High School has about 1,600 students.
Terrence Rhames, a senior at the school, said he ran to a bathroom when he heard the first shot around 8 a.m. He said he saw a girl fall out of the corner of his eye.
"I just thank god I'm safe," Rhames told The Baltimore Sun. "I just want to know who did it and who got injured."
The shooting occurred days before the national March for Our Lives event, a rally for gun control inspired by the deadly high school shooting in Parkland, Fla.