(CNN) -- The attack was shocking. Three older students pummeling a 13-year-old boy in a school bus, leaving him with a broken arm.
The video of the assault brought home its ferocity. Now, the alleged assailants are facing the consequences.
Three teenagers appeared in a juvenile court Tuesday in Gulfport, Florida. They were charged with aggravated battery.
If they had been in adult court, the charges would have constituted a second-degree felony, Judge Raymond Gross said.
"That may not mean anything to you, but that's a way of telling you this is an extremely serious charge," the judge said.
Opinion: In teen beating, don't blame bus driver
Father promises 'consequences'
As they left the courtroom, the three 15-year-olds stayed silent when asked if they had any words for the victim.
The father of one of the accused offered a few brief words: "Consequences, just consequences is all I can say."
Prosecutors say the older boys were seeking revenge after the 13-year-old told teachers that they tried to sell him drugs.
The juvenile justice department is recommending nine months probation and anger management for two of the accused.
The third, the alleged ring leader, is facing an additional robbery charge for allegedly stealing money from the victim after the beating.
Call for tougher punishment
The prosecution asked to enter the bus surveillance video as evidence to support its argument that the juvenile justice department's proposed punishments don't match the severity of the crime.
The three accused teenagers will be back in court on August 27.
All of them attended Lealman Intermediate School, a dropout prevention middle school. The attack took place July 9 in Pinellas County, Florida.
The driver of the bus, John Moody, has said he was "petrified" during the attack and has experienced nightmares about it since.
Moody, 64, retired soon after the assault, ending an 18-year career of driving buses.