Police arrested a 16-year-old boy in connection with an online post making threats of a mass shooting at Skyline High School last month.

Detectives said they also found evidence suggesting that the same teen was involved in a similar threat against Meadowdale High School in Lynnwood last spring. 

 Detectives with the Sammamish Police Department arrested the teen early Tuesday at his home in Edmonds.  Police said he had been a student at Skyline in Sammamish but moved to Edmonds last fall.

 The threat against the school, noticed on Facebook, was from someone claiming to be student at Skyline.  The student said he would take a gun to school on Thursday and "open fire on the people in the commons" until he was "taken down by school police" or until he ran out of bullets.  A picture of a gun accompanied the post.

After serving a search warrant at the home last Tuesday, detectives seized three computers and two cellphones. 

A forensic search of one of the computers found digital evidence, including a photo of a gun used in the post, linking the teen to the threat, Sammamish police said.

No weapons were found in the home.

Investigators said they found no evidence that anyone else was involved in the Sept. 18 threat against Skyline.

According to law enforcement from the city of Sammamish and the King County Sheriff’s Office the case recently came together when a number of Skyline students spoke individually to the school's resource officer with suspicions about the 16-year-old boy.

“We had several different tips that came in. It was several different tips, not a specific group,” said school resource officer Alana Hall.

Hall, the Sammamish police officer assigned to Skyline, said the suspect seemed like a normal teenager who sometimes made "poor choices."

"This is not a teenage prank, this is not a joke.  I think I can speak on behalf of the parents and the staff and the King County Sheriff’s Office when I say don't mess with the safety of our kids,” said Sheriff Steve Strachan.

Students at Skyline said the announcement of the arrest came across the PA system during fourth period on Tuesday.

The teen was booked at the King County Youth Services Center for investigation of felony harassment and cyberstalking.