Grandview High School Greyhounds Logo standing

GRANDVIEW, Wash. -- Bail was set at $2,500 Tuesday for a fourth teen arrested in connection with an alleged plot to shoot classmates at Grandview High School.

The 15-year-old boy is being held on suspicion of illegally possessing a firearm after a video was found on one of the other suspects’ phones of the boy holding a semi-automatic handgun, according to court records.

Officers found a gun at the fourth boy’s home that matched the appearance of the one in the video and took it into evidence, according to court records.

Witnesses said the boy was also seen with the other three teens when they were overheard discussing shooting people at the Lower Valley high school.

Court records show the boy has a prior conviction for theft of a firearm and being a minor in possession of a firearm. The boy was accused of stealing a handgun in 2016.

Grandview police and school officials were tipped off Friday that the students were heard talking about shooting people at the school and when would be the best time to do it, according to probable cause statements.

The other three — a 15-year-old boy, a 14-year-old boy and a 15-year-old girl — are being held on suspicion of felony harassment, with bail set at $15,000 each.