King County Sheriff’s Office deputies arrested a 14-year-old boy June 4 for investigation of felony harassment after he allegedly posted a threat to “shoot up a school lunchroom.”

The social media threat led to a lockdown Monday morning at Kentwood High School in Covington, 25800 164th Ave. SE. Deputies took the boy into custody on that Monday at Kentwood, where he is a student, and booked him into the Youth Services Center in Seattle, according to an email Tuesday from Sheriff’s Office spokesman Sgt. Ryan Abbott.

“Deputies are recommending the charge of felony harassment on the suspect, which has been sent to the juvenile prosecutor,” Abbott said. “It is up to the prosecutor what crime they actually charge the suspect with, and at this time it is unknown.”

The boy reportedly posted a message on YouTube.

“The threat was a vague threat to shoot up a school lunchroom, however, no school name was mentioned,” Abbott said.

But through extensive investigation and many interviews, deputies tracked the boy down at Kentwood. Abbott declined to say specifically how deputies determined the boy was the one who posted the message.

“After the suspect was arrested he stated it was a joke, although he realized now that it was not funny,” Abbott said.

Abbott said deputies reacted quickly when they heard about the threat.

“We take any type of threat against a school very seriously,” he said.

Kent School District and police officials placed Kentwood on a 22-minute lockdown Monday morning as part of the investigation. Once the lockdown ended with the boy’s arrest, the school district reported that all students and staff were safe.

The warning post was titled “PSA!!!,” according to the school district website.

“Our staff worked in cooperation with the Covington Police, Kent Police Department and King County Sheriff’s Office to investigate the warning post and threats behind it,” according to the school district.

The city of Covington contracts with the Sheriff’s Office for police services. Kent Police assisted on the call.

School officials want people to report any type of threat.

“We ask that the public continue to contact law enforcement to report any potential threats or suspicious activity,” according to the school district’s website. “If there is any reason to believe the safety of others is at risk, we ask that the public immediately reach out to their local police department by calling 911.”

People with safety questions or concerns can reach out to the school district.

“We want to assure you that our district and law enforcement partners continue to do everything possible to ensure our district is a safe place for our children to attend and learn. If you should have any questions or concerns, please call KSD Safety Services at 253-373-7256.”