Police have arrested four more children in connection with the arson of a bus outside a Jewish girls school in Crown Heights early on Sunday evening. The boys responsible apparently set the fire with cardboard boxes inside the bus, the door to which is open in a surveillance video of the incident.

No one was injured in the resulting fire, but the bus was gutted. Police arrested an 11-year-old boy on Monday and charged him with criminal mischief as a hate crime and arson as a hate crime. On Thursday, officers caught up to four more boys suspected to have been involved and charged them too with criminal mischief and arson, with hate crime enhancements. The boys are 11, 12, 14, and 14, all from Brooklyn.

Police say six boys were involved, leaving open the possibility of another arrest. The bus lacked writing on the outside indicating its affiliation, but did belong to a Jewish-owned company, BSD Trans Corp.

NYPD Chief of Detectives Robert Boyce told reporters on Tuesday, "It was purposefully done with prior planning. Clearly this was a religious school bus. Anyone in the community knows that."

On Thursday, Boyce said, "We spoke with the Brooklyn DA. We were both in agreement this was basically motivated because it was a local religious school that was targeted."

The bus's owner, meanwhile, didn't immediately assume to understand the motivations of the culprits.

"I am not going to jump the gun and accuse these kids of a hate crime," owner Leon Yavich told the Daily News. "I will not accuse them of a hate crime simply for the fact that I have not spoken to them."

He added, "My bus doesn’t have any Jewish markings. It doesn’t belong to the yeshiva."

Police are investigating two other events in the area as possible hate crimes targeting Jews. Last Thursday afternoon, police say someone threw a brick at a Jewish school's bus, shattering a mirror. And on Friday, a 13-year-old boy flicked rubber bands at a Jewish man, and when the man confronted him, the kid allegedly punched him in the face. The man held the boy until police arrived.