Two students and a mother leave Great Mills High School Tuesday morning. The county sheriff said parents or guardians should stay away, urging them to go instead to Leonardtown High School to reunite with Great Mills students there. Threats against schools have proliferated as well, and Great Mills High has not been immune. Heibel said the school increased its security nevertheless after social media posts about a possible school shooting "circulated quite extensively." Also last month, St. Mary's County Sheriff's office said it arrested two teenage boys for "threats of mass violence," and a 39-year-old man on related charges after the teens made threats about a potential school shooting at Leonardtown High School, a high school about 16 kilometres from Great Mills.

Source: CBC News March 20, 2018 14:58 UTC