Helicopters swept over Congo's vast jungles on Sunday, searching for the remains of dozens of people sucked out of an airplane at 33,000 feet.

Mamba Shako, Congo(search)'s health minister, said it may never be known exactly how many people fell to their deaths when the rear door of the Russian-built cargo plane burst open over the central African nation.

"At that altitude, it's not sure that we'll find bodies, but the search continues," Shako said.

He said at least 30 people are known to have safely returned with the Ilyushin 76, which swung back to Kinshasa (search), the capital.

The plane was carrying police, soldiers and their wives toward Lubumbashi (search), a city in the southeast. But only some would have been listed on the flight manifesto, common in part of the world where cargo planes are often modified to eliminate seats so more people can cram in.

Without a passenger tally, a final death toll may never be known — and official confusion continued Sunday.

A government spokesman, Kikaya Bin Karubi, said 60 passengers are missing from the plane and presumed dead. Yet the defense minister, Irung Awan, said only 14 were known to be missing — seven police and seven civilians.

Earlier, two airport officials, speaking on condition of anonymity, said 100 or more people fell from the aircraft. Survivors agreed with those numbers, saying more than 200 passengers were on the flight.

The plane is owned by the government of Ukraine, which leases it in Congo.

The Ilyushin 76 (search) is a medium- to long-range transport jet that was first flown in 1971. It is used as a civilian carrier around the world, particularly in Africa, the Middle East and Asia.

The plane has a checkered safety record, including 47 accidents that resulted in 668 deaths, according to the Aviation Safety Network (search) Web site, an air safety database.