AirAsia Flight 8501 vanished Sunday in airspace thick with storm clouds on its way from Surabaya, Indonesia, to Singapore.

Ships with sensitive sonar equipment found two large sections of AirAsia Flight 8501, Indonesian officials said Saturday.

The objects were found close together at 30 meters in the Java Sea in the sixth day of the operation. Officials told reporters that sonar located the plane parts, which are about 7.2 x 0.5 meters and 9.4 x 4.8 x 0.4 meters long. Weather conditions have stalled an effort to recover the objects.

At least 30 bodies of victims have been recovered, authorities said earlier.

Five of the victims were found still strapped in their seats, Indonesian navy official Col. Yayan Sofiyan said.

Bambang Soelistyo, head of Indonesia's National Search and Rescue Agency, said the search would be stepped up as long as the weather allowed.

"We will focus on underwater detection," said Soelistyo, adding ships from Indonesia,Malaysia, Singapore and the United States had been on the scene from before dawn today to try to pinpoint the wreckage and the all-important black boxes, or the flight data and cockpit voice recorders.

The Airbus A320 crashed into the Java Sea Sunday with 162 people on board. A number of the bodies were found by a U.S. Navy ship, said Suryadi B. Supriyadi, operation coordinator for the National Search and Rescue Agency.

Nine planes, many with metal detectors, scoured an 8,380-square-mile area off Pangkalan Bun, the closest town on Borneo island to the search area. Two Japanese ships with three helicopters are on their way to the area, Soelistyo said.

But he said bad weather, which has hindered the search the past several days, was a worry, with forecasts of rain, strong winds and high waves up to 13 feet until Sunday. The strong sea currents have kept debris moving.

He estimated that the fuselage was at a depth of about 80 to 100 feet, and vowed to recover the bodies of "our brothers and sisters ... whatever the conditions we face."

It's unclear what brought down the plane during its flight from Surabaya to Singapore. It lost contact with air traffic controllers over the Java Sea shortly after the pilots requested a change of flight plan because of weather.

There were 155 passengers on board, with 137 adults, 17 children and one infant. Also on board were two pilots, four cabin crew and one engineer, according to the airline.