A Long Beach teenager was arrested for making threats to high school classsmates on Facebook after a girl reported him to police about him on the anniversary of the Columbine school shooting.

After taking the report Wednesday officers arrested a 17-year-old Millikan High School Thursday morning on suspicion of making criminal threats and obstructing justice.

The teen, whose name was withheld, allegedly worked fast:

Cops say he had only befriended his circle of classmates a week ago before and within days “made several threats to harm the students,” according to a Long Beach police statement.

Sounds tame enough on paper, but we're guessing something about those threats made cops move quickly. LBPD:

Officers and detectives, concerned for the safety of the students and the school, worked diligently conducting interviews and gathering information from various sources. After many hours of investigation, officers learned the identity of the subject.

Cops seized the boy's computer and other electronic devices, they said. He was released to the custody of his parents.

Long Beach Chief Jim McDonnell and former LAPD honcho:

The Long Beach Police Department took immediate action upon notification of this incident to investigate the circumstances surrounding any potential for violence on the school campus. We will not tolerate any threats or behaviors with propensity for violence towards our students.

Lesson number one, cops say, is to teach kids to be careful who they befriend, even online.

LA Weekly