A sheriff says the school resource officer who shot at the suspect during a shooting at a Maryland high school is unhurt. 

Speaking at a news conference, St. Mary’s County Tim Cameron says the male student was armed with a handgun Tuesday morning when he wounded a female student and a male student just before classes began at Great Mills High School in southern Maryland.

Cameron says all three were hospitalized and the shooter was later pronounced dead at 10:41 a.m.

The principal at the Maryland high school where there was a shooting Tuesday morning told parents last month that the school had investigated threats of a possible shooting and found they were “not substantiated.”

Great Mills High School Principal Jake Heibel told parents that school officials interviewed two students in February who were overheard mentioning a school shooting and found that they posed no threat. His letter was posted on the local news site The Bay Net.

But Heibel said the school still increased its security after social media posts about a possible school shooting “circulated quite extensively.”

Story by The Associated Press with additional information from CGTN.