SKIPPACK TOWNSHIP, Pa. (AP) — Authorities in suburban Philadelphia are blaming basement sump pumps for an odor that prompted the voluntary evacuation of about 100 homes in Skippack Township.

The Montgomery County Department of Public Safety says the county hazardous response team, state Department of Environmental Protection and federal Environmental Protection Agency are working to identify the compound involved.

Reports of the noxious smell began shortly before 6 p.m. Sunday in a neighborhood and an emergency shelter was set up at the local elementary school. Some residents went to a hospital as a precaution and were released.

Residents are being asked to contact the township to have their homes tested for the presence of the compound before returning home.

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