CAMBRIDGE (CBS) – A small fire set off a hazardous materials scare late Saturday night, and investigators are still exploring the cause.

The fire started in a refrigeration unit at Cambridge Biomedical, a building owned by Harvard University.

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Soldiers Field Road was partially blocked off, and the area contained signs warning of hazardous materials.

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An environmental team was brought in and determined the scene was safe before re-opening the road.

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The fire is still under investigation.