A parent is being credited with alerting cops to a pair of teenagers who allegedly made dangerous threats. One of the kids is a student at Nevada Union High School in Grass Valley. On Wednesday, the Nevada County Sheriff's Office said the two 17-year-olds made an online threat involving a gun. On Wednesday morning, a parent heard about the threat, called the school administrators, and they called deputies who picked up the suspects. The boy and the girl were arrested and jailed. No one was hurt.