BRIDGEPORT TOWNSHIP, Mich. (AP) — A mid-Michigan township has closed its government center indefinitely after an odor made several people sick.

Bridgeport Township Fire Chief Patrick Nelson says three or four people in a front office at the Township Governmental Center reported feeling nauseous and lightheaded Friday.

Nelson tells they didn't require medical attention, and people in other parts of the building weren't affected.

He says the offices will remain closed until environmental testing crews can assess and identify the source of the odor.

Nelson said the odor isn't persistent. Tests performed with his department's hazmat equipment detected nothing unusual.

Nelson says the government center was built atop a landfill in the 1970s.