Maryland: A Maryland high school was on lockdown following a shooting on Tuesday morning, the local school district said in a statement, but the incident has since been "contained."
The shooting took place at Great Mills High School in St. Mary`s County, and it was not clear whether there were injuries.
It occurred amid a re-energized national debate over school shootings in the United States following an attack on Feb. 14 at Marjory Stoneman Douglas High School in Parkland, Florida, where a gunman killed 17 students and faculty.
The St. Mary`s County sheriff`s office confirmed an incident at the school and urged parents in a Twitter post not to approach the school. Federal investigators from the Bureau of Alcohol, Tobacco, Firearms and Explosives were heading to the school, the agency said.
Great Mills is a town about 70 miles (110 km) south of Washington.