PORTLAND (WGME) -- Casco Bay High School dismissed its students early Friday due to a large flu outbreak.

The school says more than 40 percent of students and staff were absent Friday, leading the Maine CDC to declare an outbreak of the flu.

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The threshold for an outbreak is 15 percent of students and staff absent with a specific illness.

Casco Bay High School sent students home at 11:50 a.m. Friday due to the outbreak.

“We anticipate the weekend will allow enough recovery time for us to resume normal operations on Monday," Casco Bay Principal Derek Pierce said. "We will keep you updated and let you know if circumstances change.”

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The school is still expected to reopen on Monday.