A fire that burned about 35 acres of grass and brush in Swanville on Sunday was accidentally set by a group of teenage boys, officials said.

The three teenagers were apparently using fire to thaw ice around a frozen container, but the dry grass ignited, resulting in a blaze that took about 30 local firefighters to extinguish, Belfast Fire Chief Jim Richards told the Bangor Daily News.

Richards said the teens will not face charges in connection with the blaze.

“They felt bad. They knew they’d made a stupid mistake,” Richards told the BDN. “They helped the guys fight the fire for three hours.”

The fire scorched grass and brush off Oak Hill Road near the northwest corner of Hurds Pond.

Firefighters from Belfast, Morrill and Thorndike responded to the scene at about 10:15 a.m. on Sunday.

No injuries were reported.

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