MINNEAPOLIS (AP) — The smell of propane caused officials to evacuate a University of Minnesota building where a student was injured in a science lab explosion last week.

University spokeswoman Julie Christensen says someone in Smith Hall smelled propane Wednesday morning, pulled the fire alarm and called 911. About 100 people were evacuated.

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Minneapolis firefighters ventilated the building and gave the all-clear. The source of the propane smell was not identified.

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About a week ago, a chemistry student was injured when a chemical compound mixture exploded.

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