LAKEPORT, Mich. -- Crews have plugged all fuel valves and vents on a barge that sank in stormy Lake Huron, preventing more fuel from spilling, and people nearby are being warned to stay indoors as much as possible to avoid fumes, the Coast Guard said Friday.

A 110-foot dredging barge sank early Thursday, and the tug pushing it overturned, spilling an unknown amount of diesel fuel. The Coast Guard said crews suspended work late Thursday until daylight Friday, when they returned.

"There is still a strong diesel odour in the air, so residents and visitors of the lower Lake Huron area are encouraged to avoid areas where there is an odour in the air," the Coast Guard said in a statement.

No injuries were reported. The Coast Guard said the remaining fuel should be secured after the vents were plugged late Thursday.

The Coast Guard said fuel from the barge reached the Michigan shoreline near Lakeport State Beach, about 65 miles northeast of Detroit. Cleanup efforts continue on Friday, and there were no reports of wildlife affected by the spill. Some area beaches were closed.

"The impact to the shoreline has been minimal ... but there has been no report of a thick product wash ashore," the Coast Guard said.

It wasn't known what caused the Arthur J. to sink near the southern end of the lake, just over a mile from the Michigan coast.

The barge and the 38-foot tug Madison both were partially submerged in 22 feet of water nearly six miles north of the entrance to the St. Clair River, which links lakes Huron and Erie. Commercial traffic had not been affected because the stricken craft are outside the shipping channel, but the Coast Guard advised mariners in the area to be cautious.