CORONADO, Calif. -- A threat of violence made on social media prompted a brief lockdown at Coronado High School Thursday morning and left a student under arrest.
The security alert at the campus near Spreckels Park went into effect shortly before 10:30 a.m., according to police.
Teachers kept all students secured in their classrooms while officers conducted a sweep of the school at 650 D Ave. Police gave an all-clear about 11 a.m.
Authorities identified the source of the online post as a 16-year-old student who had stayed home from school. Officers went to the boy's Coronado home and took him into custody without incident.
The suspect, whose name was withheld because he is a minor, was booked into juvenile hall on suspicion of issuing criminal threats.
In a joint statement, Coronado Police Chief Jon Froomin and city schools Superintendent Karl Mueller said they wanted "to remind our students and families that threats are a serious matter."
"Threats are considered a felony, a crime punishable by imprisonment," they stated. "In addition to criminal punishment, students who make threats are subjected to district disciplinary consequences."