A teen armed with a sword and chainsaw who had several pipe bombs strapped to his body was arrested Monday after two explosions rocked Hillsdale High School in San Mateo, Calif., KTVU reported.
Police called the foiled attack that forced the evacuation of more than 1,200 students and teachers a Columbine-style plot, according to the station.
San Mateo Police Chief Susan Manheimer told KTVU that the 17-year-old boy came onto campus with the chainsaw, a 2-foot-long sword and 10 homemade pipe bombs attached to a tactical vest he was wearing.
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He detonated two of the pipe bombs in an empty hallway near the library, and the smoke activated a fire alarm, Manheimer said.
Authorities fielded several calls from Hillsdale High School beginning at 8:07 a.m. about a gunman on the grounds, the station said. Shortly thereafter, reports came in of an explosion inside the school.
Two teachers heard the explosions, ran into the hallway and confronted the teen, who then fled, Manheimer told KTVU. A third teacher caught up with the boy and tackled him, according to police Lt. Mike Brunicardi. Another arrived a minute later with school Principal Jeff Gilbert to help hold the suspect down.
Brunicardi called the actions by Gilbert and the teachers "simply heroic," according to KTVU.
"All the while that the teachers and principal are confronting this kid, holding him down and tackling him, he's got eight live pipe bombs attached to his person," Brunicardi said.
No one was hurt in the explosion and no gun was found, according to Manheimer.
The incident prompted the evacuation of about 1,270 Hillsdale students and several teachers.
Classes were canceled for the day as police and bomb squad units searched the premises to ensure no additional devices had been planted on school grounds.
The teen is currently classified as an uncharged minor, meaning authorities are not identifying him, San Mateo Assistant District Attorney Karen Guidotti told FOXNews.com.
He is in custody at the juvenile detention center while the district attorney's office awaits the full investigative report from police, she said. When they receive it, they will decide whether or not to charge him as an adult.
Guidotti said the boy is a former student at the high school but did not graduate from Hillsdale.