By CBS3 Staff

UPPER SAUCON TOWNSHIP, Pa. (CBS) — Hotel guests have been let back into their rooms after a possible hazmat situation forced an hours-long evacuation of the SpringHill Suites in Upper Saucon Township, Lehigh County. Crews were called to the hotel at 3800 West Drive in Center Valley around 8 p.m. Thursday for a report of a strong odor.

The building was immediately evacuated.

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(Credit: CBS3)

Officials say tests by hazardous materials teams came back inconclusive.

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Some people experienced minor irritation and were checked out at the hospital. They have since been released.

Authorities gave the all-clear just before 6 a.m. Friday.

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There is no word on what caused the odor at this time.