Three people broke into Chinook Elementary School early Halloween morning and sprayed a fire extinguisher inside, according to the Anchorage Police Department.

School security responded just after 4 a.m. to a security alarm. Not long after, a fire alarm was activated, police said. The trio appeared to enter through a window before setting off the fire extinguisher. Once security arrived, the group ran away from the scene.

Police are not releasing further information on the vandals at this time.

Anchorage School District spokesperson Morgan DuClos said the rough estimate of damage is $2,500. 

"The District is grateful to community partners for their vigilance and asks that everyone remain attentive to activity so that schools remain safe, great places to learn and enjoy," DuClos wrote in an email.

The investigation is ongoing.

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