Firefighters were called to the school around 8 p.m. Sunday.
They quickly called a second alarm bringing in reinforcements.
Video in the media player above is from a previous update
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A district spokesperson says the fire is not impacting classes on Monday, but the gym is being blocked off.
It's primarily used for practices with the school's sports teams.
School officials released a statement writing:
"Good evening Amador community,
We're grateful to our local fire authorities for containing the fire to the small gym - no other areas of campus were affected. As a precaution, PG&E switched off power to a majority of the campus. Once the fire inspector has cleared the building, power will be restored to campus which we anticipate will occur by Monday morning.
We anticipate school will resume as normal tomorrow with the exception of activities planned inside the small gym. Please stay tuned for more information and necessary adjustments. A perimeter will be set up around the small gym for student safety - please do not cross these barricades or attempt to go near the gym for your safety.
Thank you for your patience and support."
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