KUALA LUMPUR, Malaysia — An air search in the southern Indian Ocean for possible objects from the missing Malaysia Airlines plane described as the “best lead” so far ended without success but will resume Friday, Australian rescue officials said.

The four planes were checking to see if two large objects spotted in satellite imagery bobbing in the remote ocean were debris from Fight 370 that disappeared March 8 with 239 people on board.

One of the objects was almost 80 feet in length and the other was 15 feet. There could be other objects in the area, a four-hour flight from Australia’s southwestern coast, said John Young, manager of the Australian Maritime Safety Authority’s emergency response division.

“This is a lead, it’s probably the best lead we have right now,” Young said. He cautioned that the objects could be seaborne debris along a shipping route where containers can fall off cargo vessels, although the larger object is longer than a container.

Authorities said the four planes searched an area of 8,800 square miles about 1,550 miles southwest of Perth without success.

News that possible plane parts had been found marked a new phase in the emotional roller coaster for distraught relatives of the passengers, who have criticized Malaysia harshly for not releasing timely information. While they still hope their loved ones will somehow be found, they acknowledged that news of the possible debris could mean the plane plunged into the ocean.