UPDATE: Friday's lockdown at Sequatchie County High School's has been lifted following a threat made on social media.

Sequatchie County Sheriff Ronnie Hitchcock says a former student, 19-year-old Zachary Damian Key, made threats on Snapchat that he was going to shoot up the school. 

The school was placed on lockdown while deputies searched for Key.

He was been found and arrested for filing a false report.

Key is being held at the Sequatchie County Jail without bond as the investigation continues.

Stay with WRCBtv.com for updates to this story.

PREVIOUS STORY: Another online threat has caused a Tennessee Valley school to be locked down, out of an abundance of caution.

A threat on social media prompted officials to lock down Sequatchie County High School Friday, according to Sequatchie County School Superintendent Pete Swafford.

Swafford tells Channel 3 he hopes to have the situation resolved quickly.