The students were waiting at the bus stop after class in the city of Bekasi, when the truck veered toward them and crashed into two motorcycles and toppled a concrete communications tower, traffic policeman Latif Usman said.
Usman said a further 20 children were injured.
“We are conducting an investigation to assess if the brakes failed,” Usman said.
Another police official in Bekasi said the driver had been detained.
Images from the scene showed the communications tower had fallen across the road outside the school’s gates and crashed into the bus stop on the sidewalk.