Aircraft returned to the southeastern Bahamas early Sunday to resume the search for a U.S. cargo ship with 33 people on board that lost power and communications when it was caught in Hurricane Joaquin and has not been heard from since.

U.S. Coast Guard, Navy and Air Force planes and helicopters were expected to spend the day looking for the ship across a broad expanse of the Atlantic Ocean around Crooked Island, which the ship was passing when it was battered by fierce winds and waves by what was then a Category 4 hurricane.

The Coast Guard on Saturday located a life ring from the 790-foot cargo ship but turned back at nightfall. The storm has moved out of the Bahamas and was heading toward Bermuda but the pilots were still contending with high winds and low visibility that made the search difficult and dangerous, said Petty Officer First Class David Schuhlein.

"Our hope is that we can really saturate that area better than yesterday," said Schuhlein, a Coast Guard spokesman.

The El Faro departed from Jacksonville, Florida on Sept. 29, when Joaquin was still a tropical storm, with 28 crew members from the United States and five from Poland. The ship was heading to Puerto Rico on a regular cargo supply run to the U.S. island territory.

The ship's operator, TOTE Maritime Puerto Rico, said the El Faro said it had told family members of the crew not to be discouraged by the discovery of a life ring, saying it may help authorities narrow the search and locate the vessel.

"While this reflects that the ship was caught in rough seas and extreme weather, it is in no way indicative of the ship's fate," the company said in a statement. "Small items such as life rings and life jackets are lost at sea frequently, particularly in rough weather."