WASHINGTON, March 20 (Xinhua) -- A high school shooting in the U.S. state of Maryland Tuesday has resulted in the death of the shooter and two other injuries, local authorities said.

"There has been a shooting at Great Mills High School. The school is on lock down, the event is contained, the Sheriff's office is on the scene," St. Mary's County Public Schools said.

According to local sheriff's office, a male student opened fire at a girl in the hallway shortly after school started, injuring another male student in the process.

The shooter was killed in gunfight with a school resource officer who was alerted to the shooting by students and stuff, but the sheriff's office has yet to determine whether the gunman killed himself or was killed by the safety officer.

St. Mary's County Sheriff Tim Cameron said the resource officer and the gunman each fired a round of bullets after engagement.

Both victims have been transferred to a local hospital, Cameron said, adding that the girl was in critical condition while the male student was in stable condition.

Other students of the school were evacuated to another school to be reunited with their parents.

School principal Jake Heibel has warned of a shooting threat weeks prior to the incident, but concluded that the threat was "not substantiated" after investigation. It is unclear whether the threat was linked to the actual shooting.

The incident took place just a month after a tragic shooting in a high school in the southern state of Florida claimed the lives of 17 people.