BUFFALO GROVE, Ill. (STMW) – Four teens told Buffalo Grove police that they were just trying to stay warm and did not mean to burn an entire playground in the northwest suburb.

Buffalo Grove police arrested two 14-year-old Buffalo Grove boys and a pair of 14-year-old girls, one from Buffalo Grove and one from Wheeling Nov. 11 in connection with the Nov. 5 arson that destroyed the playground of the Alcott Center, the Buffalo Grove Park District’s headquarters at 530 Bernard Drive.

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Officials estimate the park district will need to spend $100,000 to replace the playground.

All of the four teenagers will face felony charges of arson and criminal property damage in Cook County Juvenile Court.

“They started the fire, they said, to keep warm,” Buffalo Grove police Cmdr. Steve Husak said Friday. “The fire ended up burning the equipment.”

He said that the group had been out that evening, walked to the park and found a collection of dry leaves under a sewer grate.

Lt. John Gilleran, a Buffalo Grove Fire Department spokesman, said the teenagers gathered more leaves from the area, as well as needles that had fallen from two nearby pine trees, and set that mixture ablaze.

“Those make excellent tinder,” he said of the pine needles, and the teenagers quickly had more heat than they knew how to handle.

Gilleran said a nearby video camera showed the two boys grabbing the lid from a trash can and covering the sewer grate with it, but the lid was made of fiberglass, caught fire and helped the flames spread to the playground’s rubber walking service.

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Buffalo Grove Park District spokesman Mike Terson said the surface was supposed to be flame-resistant.

Gilleran said that even though the fire burned much of the surface and the equipment, the material had done its job.

“That rubber matting did not melt anywhere as much as you would think it would,” Gilleran said. “That stuff actually held up pretty good.”

The temperature reached around 1,300 degrees, he said, and melted four of the playground’s eight aluminum poles.

The equipment was covered by a plastic coating that helped made it accessible to children with disabilities.

Gilleran said that coating burned, helping the fire spread. The video shows the two boys wearing hooded sweatshirts.

Gilleran said firefighters had no indication that the youths used any outside fuel to burn the park.

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Husak said the two boys face separate charges for allegedly being caught on video damaging chairs earlier that day at Emmerich Park. He said police received tips from the public, which led them to the four.