After a teenage gunman killed 17 people at a Parkland, Florida, high school last month, schools across the country were hit by a wave of copycat threats.
In Colorado, at least two high school students were arrested based on information sent to the state anonymous tip line and mobile app, known as Safe2Tell . “They had a list, they had weapons, they knew exactly what they wanted to do,” said Colorado Attorney General Cynthia Coffman, whose office administers the program.