The children attended a nearby school, which had been operating without an educational license. It is suspected that the vandalism was motivated by religious intolerance, which was likely being taught at the school.

The mayor of Solo, Gibran Rakabuming Raka, expressed anger upon learning that there was a religious motivation for the vandalism committed by children. 

The city administration reported the school’s administrators and teachers to the police for motivating a suspected hate crime. The thirty-nine children who attend the school will receive counseling. Indonesian public opinion condemns this act of religious intolerance, and many are calling for an investigation into the school to check for possible indoctrination by educators.

Source: persecution.org