The Coast Guard continued its search Wednesday afternoon for the captain of a towing vessel that capsized and sank earlier that morning in the Mississippi River near Norco.

The incident happened around 12:30 a.m. at mile marker 126 of the river, according to Ensign Frank Bullock, a Coast Guard spokesman. The 52-foot towing ship—called Gate Way—capsized for unknown reasons and eventually sank.

Another towing vessel in the area rescued the boat's one crew member, who was later released to the care of a relative.

The Coast Guard said it has three boats and a helicopter searching for the missing man.

"We will continue to actively search for the mariner and that part of the investigation entails not only finding out what happened in this accident, but attempting to prevent that accident from occurring in the future," Bullock said.

Bullock said the Coast Guard would continue searching for the missing boat captain as long as there was still a chance of finding him.

Neither the captain nor the surviving crew member's names have been released.