Associated Press

KUALA LUMPUR, Malaysia — Malaysia's government said Thursday that two more pieces of debris, discovered in South Africa and Rodrigues Island off Mauritius, are "almost certainly" from Flight 370, bringing the total number of pieces believed to have come from the missing Malaysian jet to five.

The aircraft mysteriously disappeared more than two years ago with 239 people on board, and so far an extensive underwater search of a vast area of the Indian Ocean off Australia's west coast has turned up empty.

Though the discovery of the debris has bolstered authorities' assertion that the plane went down somewhere in the Indian Ocean, none of the parts thus far has yielded any clues into exactly where and why the aircraft crashed. Those elusive answers lie with the flight data recorders, or black boxes, which may never be found, said Geoff Dell, a specialist in accident investigation at Central Queensland University in Australia.

"It shows they're looking in the right ocean — that's about it," Dell said.

The two newly identified pieces of debris were found in March. Malaysian Transport Minister Liow Tiong Lai said one is an engine cowling piece with a partial Rolls-Royce logo, and the other is an interior panel piece from an aircraft cabin — the first interior part found from the missing plane.

"As such, the team has confirmed that both pieces of debris from South Africa and Rodrigues Island are almost certainly from MH370," he said in a statement.

All five pieces have been found in various spots around the Indian Ocean. Last year, a wing part from the plane washed ashore on France's Reunion Island. In March, investigators confirmed two pieces of debris found along Mozambique's coast were almost certainly from the aircraft.

The jet, which vanished on March 8, 2014, while flying from Kuala Lumpur to Beijing, is believed to have crashed somewhere in a remote stretch of the southern Indian Ocean about 1,100 miles off Australia's west coast. Authorities had predicted that any debris from the plane that isn't on the ocean floor would eventually be carried by currents to the east coast of Africa.