(Pleasant Grove-AP) -- One ninth-grader is under arrest and police say they're arresting two more in connection with threatening graffiti found at Pleasant Grove Junior High School.

The message scrawled on a girl's restroom wall said a gun would be brought to school today. The threat prompted school officials to ban backpacks for the day and to limit entry to the school.

About ten officers also patrolled the campus today.

Pleasant Grove police say they've arrested a ninth grade girl. She faces charges of making a threat against life or property and criminal mischief, both misdemeanors.

Police also expect to arrest two other ninth graders. They say the students just wanted to get out of going to school.