By CBS3 Staff

READING, Pa. (CBS) — Twenty people were taken to the hospital Friday after a hazmat situation at a YMCA in Reading. First responders were dispatched to the YMCA located at 631 Washington St. around 3 p.m.

Fire officials say 21 people were injured and 20 people were taken to the hospital for evaluation. They’re all expected to recover.

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According to the Reading Fire Department, two YMCA staff members mixed two wrong chemicals together in the first-floor pool area, which lead to the emergency incident.

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The two staff members were among the 20 people taken to the hospital.

Overall, 81 people were evacuated from the YMCA.

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The YMCA is investigating how the two chemicals were mistakenly mixed.