(AP) – Kentridge High School near this south Seattle suburb was locked down for nearly three hours Friday afternoon after authorities received an apparently bogus report that a student had a gun. An 18-year-old former student at the school was arrested for making a false report, and officials determined there never was any danger, said King County sheriff’s spokesman Sgt. John Urquhart. A 911 call about 1:30 p.m. came from a male who identified himself as a 15-year-old student, and who said he saw another student entering the school with a gun in his waistband. Students were locked in their classrooms while a SWAT team searched the school. Nothing was found, although the student identified as having the gun was located. “He’s not involved at all,” Urquhart said. The caller’s motive wasn’t immediately known, and there wasn’t immediately any information that he even knew the person mentioned in the phone call, Urquhart said. The 18-year-old was arrested about 4:30 p.m. Urquhart would not disclose how he was tracked down other than “good police work.” Urquhart said that teen, who was not immediately identified, was being booked for investigation of obstructing and filing a false report.