Salvage work continued late Saturday on a partly submerged coal barge pinned to a pier of the

MacArthur Bridge, which carries railroad traffic over the Mississippi River at the southern end of downtown St. Louis.

The barge was wrapped around the pier near the Illinois side of the river, said Coast Guard Lt. Rob McCaskey. A second barge was submerged and stuck against the bridge pier near the Missouri bank. As a result, about four miles of the river was closed to barge traffic because of concern that the barges protruded into the navigation channel.

Both barges were part of a 15-barge tow that broke apart about 11:30 a.m. Saturday as it headed downstream near the Gateway Arch. All 15 barges owned by American Commercial Lines were filled with coal loaded in St. Louis, the Coast Guard said.

Workers recovered the remaining barges downstream and moved them to the side of the river.

No cause for the accident had been determined, but the Mississippi rose above flood stage early Saturday. The National Weather Service said the river will rise until 1 p.m. Monday, when it should crest at 35 feet, which is five feet above flood stage in St. Louis.