Detroit - Salvage crews trying to free a grounded barge south of Detroit couldn't do it Saturday with five tugboats and so they'll try at daybreak on Sunday with seven tugs, a U.S. Coast Guard spokesman said.

"They're hoping to get 14 to 15 thousand horsepower on it," after failing with the 10,000 h.p. of five tugs, Lt. Justin Westmiller said.

Crews called off efforts Christmas morning while awaiting two more tugs from Cleveland, he said.

The barge, with a 29,500-ton capacity, ran aground at 3:13 a.m. EST on Friday - in a part of the Detroit River called the Trenton Channel - as it delivered coal from Toledo to a Detroit Edison generating plant in Trenton, the Coast Guard said. Five tugs managed at about 8:30 p.m. Friday to momentarily free the massive McKee Sons, a former lake freighter converted to a combined tug-barge, but it ran aground again.

"There's no threat of blocking any shipping traffic, and no threat of causing any pollution," Westmiller said Saturday.

The 780-foot McKee Sons is about 100 yards offshore, he said. The crew of about two dozen had plenty of provisions for having Christmas dinner aboard, Westmiller said.

The boat's pilot might have made a navigation error to causing the grounding, apparently in mud, he added.