PEARCE AIR FORCE BASE, Australia - A Chinese military aircraft scouring the southern Indian Ocean for possible wreckage from the missing Malaysia Airlines plane reported seeing objects in the water Monday, after data recorded by a French satellite gave credence to the view that Flight 370 might have fallen into the sea there, far off the coast of western Australia.
About two-thirds of the 227 passengers onboard the flight, which vanished on March 8 after leaving Kuala Lumpur bound for Beijing, were Chinese nationals, and the Chinese government has been particularly vocal in demanding an intense hunt for any signs of the missing Boeing 777-200. No definitive evidence has been found so far.
A brief bulletin from a Chinese Air Force IL-76 plane that has joined the search off western Australia appeared to bolster hopes that traces of the plane might yet be found. But the description of the sighting Monday was vague, and it seemed entirely possible that it could prove to be another in a long list of false leads.
"The crew of a Chinese IL-76 plane spotted some suspicious objects in the southern Indian Ocean on Monday," said a report from Xinhua, the Chinese state-run news agency, which had a reporter on the plane.
The plane spotted a number of objects, including two large pieces, Xinhua reported. "From a height of 1,000 meters, there were two quite large objects, and some small, white fragments scattered within a radius of several kilometers," the report said.
The Australian Maritime Safety Authority, which is coordinating the search off western Australia, said in a statement that it had been "advised about the reported objects sighted by a Chinese aircraft." It said the "reported objects are within today's search area and attempts will be made to relocate them."
Earlier, the Xinhua reporter onboard the Chinese search plane had said that visibility was "quite poor" because of low-hanging clouds.
The Chinese government has directed a polar exploration vessel, Xuelong, to the search area in the southern Indian Ocean. Xinhua said the ship was heading to the vicinity of the latest sighting of unusual objects, but would not get there before Tuesday morning.
Australia and China have already released blurry satellite images of objects floating in the search area, and officials said those might be wreckage from the Boeing 777-200. On Sunday, a French satellite was also reported to have detected objects in the southern Indian Ocean that might be related to Flight 370. France's Ministry of Foreign Affairs said the possible debris was spotted using satellite-based radar, but gave no other details about the image or the objects' precise location.
The recent announcements appeared likely to reinforce a belief that the plane fell into the ocean far off western Australia after veering sharply from its planned route. Investigators say they believe military radar and satellite signals indicate the plane cut across mainland Malaysia, headed west over the Indian Ocean and then possibly south, toward the area where Australia has now organized a search involving New Zealand and the United States. Britain, China and Japan have also sent military planes and ships to aid the hunt.
Flight Lt. Russell Adams, the pilot of an Australian P-3 military aircraft that spent more than 10 hours on Sunday searching for debris, said weather conditions had deteriorated in parts of the search zone.
"There was cloud down to the surface," he told reporters Sunday, minutes after landing at the base here, which is about 30 miles north of the western Australian city of Perth.
The search is focused on an area about 1,550 miles southwest of Perth. On Monday, Australian authorities said 10 aircraft would be involved in the search, including a U.S. Navy P-8 Poseidon, two Chinese transport aircraft and two Japanese patrol planes, all departing from the Air Force base here.
China has described the "unusual object" sighted by one of its satellites Tuesday as measuring about 74 feet by 43 feet. It was observed about 65 nautical miles southwest of the spot where, two days earlier, another satellite had captured similar images of floating objects, which the Australian government said might be wreckage from Flight 370.
Experts on satellite imagery and open-ocean recovery said those two sightings might be of the same object or objects, and that might give the search teams more information with which to calculate ocean currents and drift speeds, turn back the clock and estimate where the plane might have struck the ocean sometime after 8 a.m. Malaysia time on March 8.