MINNEAPOLIS (WCCO) — Playgrounds are the fun part of any neighborhood school, where kids enjoy themselves and neighbors gather.

But when students return next Monday to the Lake Harriet Lower Elementary School, the normal laughter of kids at play could be silent.

READ MORE: Protesters Demonstrate Against 'Unethically High' Drug Prices Outside UnitedHealthcare Corporate Offices

It was just before noon on Sunday when neighbors noticed the playground consumed by a massive fireball.

“It’s very upsetting, I couldn’t believe it. I said to my son, ‘The playground is on fire,’ and he looked at me like, ‘You’re crazy,’” Ulrike Calaba said.

The sprawling play area is covered with a base of shredded tire fragments. The rubber only helped fuel the fire along with the playground’s component parts made of plastic.

“It was really scary looking and a huge plume of smoke,” said Calaba, who was trying to bring her granddaughter to the park to play. “It was a fierce fire.”

Investigators say several boys admitted to playing with matches near the swing set. They apparently started a small fire in the rubber tire fragments they couldn’t stomp out.

On Monday, parents and their children stopped by to see the damage — one week before students return to classes.

READ MORE: Bemidji Police Asking For Public's Help Locating Missing Teeen, Sian-Rose Tappo

“These are kindergartners, the smallest kids through third graders,” said Jenny Floria, a parent. “And when it comes time for recess, they’re going to want a place to let off some energy and it’s gone.”

District officials stopped to photograph the damage for insurance purposes. A district spokesman says it may take six to eight weeks to replace damaged playground components.

The fire burned so hot that it melted aluminum posts, which support the plastic tubes and slides.

Floria says she feels worst for the newest kids to the school.

“It’s just a hard way to start the school year,” Floria said. “I think about families with kindergartners in particular – it’s your first kid and you are sending them off to school, and by the way you don’t get to play at recess.”

There is no estimate on the dollar amount of damages or when repairs might begin.

MORE NEWS: Supply Chain Issues: 'There Really Are Problems Everywhere,' Even For Small Companies

Police say they have spoken to the parents of the boys believed responsible for the fire, but say it is unclear if the district may hold them responsible.