A motorcycle convoy of hundreds of high school students celebrating their graduation turned violent in Klaten, Central Java, on Tuesday afternoon.

Three students were stabbed while a number of food stalls and vehicles were destroyed by the students who were riding dozens of motorcycles around the city.

In Jetis village, South Klaten subdistrict, the students, who wore uniforms covered in spray paint messages and scribbles, ran amok and destroyed bamboo fences that were being repaired by locals.

“Villagers and the workers warned them but they became even crazier,” Jatmiko, 32, a local, said. He added that the students also threw rocks, woods, and iron pipes at anything they passed by.

Eventually the police came and secured the group. Some managed to flee but most of them were arrested, said Darmadi, 60, another local.

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Klaten Police Deputy chief Com. Heri Sutanto said the police had arrested hundreds of students who took part in the convoy and were investigating how the spree of destruction began.

“They were just riding around at first, but somehow it turned destructive and violent, even leading to stabbings,” Heris said on Wednesday.

The police confiscated sharp weapons, iron clubs and bike gears. Three students of SMAN 1 Senior High School Klaten were stabbed while two other teenagers were wounded on the face and shoulder.

High school students nationwide underwent the national exam on April 11. (hol/bbs)