SANTA ANA (CBS) — Western Medical Center in Santa Ana was evacuated Saturday evening because a gas-like odor was detected.

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The incident happened at about 8:15 p.m., according to Capt. Ben Gonzales of the Santa Ana Fire Department.

“At this time we are returning some of the patients to the emergency room,” Gonzales said. “We still are systematically going floor by floor looking with our HazMat team to see if we can determine the exact cause of the odor itself.”

Gonzales said rescuers and hospital staff were able to get the building fully evacuated in about 20 minutes, getting the 75 to 100 people inside to safety.

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HazMat crews told KCAL9 and CBS2 that they were unable to determine the exact cause or what the substance was.

No injuries were reported.

All floors were cleared for the return of patients by 10:30 p.m.

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