(CNN) -- A Chinese patrol ship searching for signs of Malaysia Airlines Flight 370 in the southern Indian Ocean discovered Saturday the pulse signal used by so-called black boxes, state news agency Xinhua reported.
But the pulse signal has not been confirmed, China's Maritime Search and Rescue Center reported, according to China Communications News, which is the Ministry of Transport's official newspaper.
The signal reported -- 37.5 kHz -- "is the standard beacon frequency" for the plane's cockpit voice recorder and the flight data recorder, said Anish Patel, president of pinger manufacturer Dukane Seacom.
The frequency was chosen for use in the recorders "to give that standout quality that does not get interfered with by the background noise that readily occurs in the ocean."
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But he said he would like to see more evidence. "I'd like to see some additional assets on site quickly -- maybe some sonobuoys," he said, referring to 5-inch-long (13-centimeter) sonar systems that are dropped from aircraft or ships.
And he said he was puzzled that only one signal had been detected, since each of the recorders was equipped with a pinger, which is also called a beacon.
Other experts cautioned that no confirmation had been made that the signal was linked to the missing plane.
"We are unable to verify any such information at this point in time," the media office of the Joint Agency Coordination Centre said in an e-mail.
"We've had a lot of red herrings, hyperbole on this whole search," said oceanographer Simon Boxall, a lecturer in ocean and earth science at the University of Southampton told CNN. "I'd really like to see this data confirmed."
If this proves to be what investigators have been searching for, "then the possibility of recovering the plane -- or at least the black boxes -- goes from being one in a million to almost certain," he said.
But, he added, "It could be a false signal."
CNN aviation analyst David Soucie was less skeptical. "This is a pinger," the airplane accident investigator said. "I've been doing this a lot of years, and I can't think of anything else it could be."
Xinhua said the detector deployed by the Haixun 01 patrol ship picked up the signal around 25 degrees south latitude and 101 degrees east longitude. "It is yet to be established whether it is related to the missing jet," it said.
Committees being formed
The announcement came nearly a month after Malaysia Airlines Flight 370 disappeared, and on the same day that the nation's acting transportation minister said three committees were being formed to tackle the disappearance of the flight.
One will tend to the families of passengers aboard the missing flight, the second will oversee the investigation team and a third committee will handle the deployment of assets, said Hishammuddin Hussein.
Malaysia will also appoint an independent investigator to lead an investigation team, the acting minister said.
The team will include an airworthiness group, looking at issues such as maintenance records, and an operations group to examine aspects such as flight recorders and operations. A medical and human factors team will investigate issues such as psychology, he said.
As well as Malaysia and Australia, the team will include representatives from China, the United States, the United Kingdom and France, he said.
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Hishammuddin also addressed "unfounded allegations made against Malaysia," which, he said, "include the extraordinary assertion that Malaysian authorities were somehow complicit in what happened to MH370."
He added, "I should like to state, for the record, that these allegations are completely untrue."
Hishammuddin pointed to a statement from the Association of Southeast Asian Nations, which says Malaysia has "done its level best" in its response to an operation that "is the biggest and most complex we have ever seen."
The minister, who had earlier briefed ASEAN ministers and the United States on the search at a joint defense forum, thanked the United States for its "unwavering support" and said the ASEAN ministers had pledged their continued cooperation.
The hunt for physical evidence continues Saturday -- both on the surface of the southern Indian Ocean and deep below it.
The British submarine HMS Tireless is now in the search area, Hishammuddin said.
Meanwhile, a parallel search for digital clues on the hard drives of a flight simulator in the home of one of the pilots turned up nothing conclusive.
There was no "we got it" information, a U.S. official with knowledge of the investigation told CNN late Friday.
There were some "curious" things, given the situation, the official said. The captain, Zaharie Ahmad Shah, had programmed several alternate routes into the simulator, but it appeared he had done so to come up with safe plans of action in case of emergencies aboard the plane, the official said.
The searches appear to be what an experienced and professional pilot would do, the official said.
Race against time to find pingers
In the choppy waters of the Indian Ocean, the hunt is not letting up.
The British Royal Navy survey ship HMS Echo and the Australian naval supply ship Ocean Shield began searching for the plane's pingers and possible wreckage about 6,500 feet to 13,000 feet deep on the ocean floor Friday.
The search was along a single 150-mile (240-kilometer) track, said retired Air Chief Marshal Angus Houston, the head of the Australian agency coordinating the operation.
The race is on to find the missing Boeing 777's locator pingers before their batteries expire.
The acoustic pinger batteries on Flight 370's black boxes were due to be replaced in June, the Malaysia Airlines chief executive said Saturday.
"We can confirm there is a maintenance program. Batteries are replaced prior to expiration," Ahmad Jauhari Yahya said.
The Ocean Shield has high-tech gear borrowed from the United States. That includes a Bluefin-21, which can scour the ocean floor for wreckage, and a Towed Pinger Locator 25, with its underwater microphone to detect pings from the jet's voice and data recorders as deep as 20,000 feet (6,100 meters).
"It is a very slow proceeding," U.S. Navy Capt. Mark M. Matthews said of the second tool, which is towed behind a vessel typically moving at 1 to 5 knots.
Bill Schofield, an Australian scientist who worked on developing flight data recorders, said: "If they do find it, I think it'll be remarkable."
Up to 10 military planes and three civilian aircraft -- in addition to 11 ships -- will be looking Saturday for any sign of Flight 370, according to the Australian government.
The search area will be just under 84,000 square miles (217,000 square kilometers), which is slightly less than the area searched Friday, and will focus some 1,050 miles northwest of Perth. This is about 50 miles farther from the western Australian city than was the case a day earlier.
Is this the right spot? Will they find anything? So far, all efforts to find signs of the airliner have proved unsuccessful. Still, those involved have vowed to keep trying.
"Really, the best we can do right now is put these assets in the best location -- the best guess we have -- and kind of let them go," U.S. Navy Cmdr. William Marks told CNN. "Until we get conclusive evidence of debris, it is just a guess."
'Long way to go'
Officials have repeatedly warned that the massive international search to find signs of the Kuala Lumpur-to-Beijing flight may not conclude anytime soon.
In the case of Air France Flight 447, which crashed into the Atlantic Ocean in 2009, officials found debris on the surface after five days of searching. But it took them nearly two years to find the main pieces of wreckage, the flight recorders and many of the bodies of those on board.
With Flight 370, the search teams have even fewer clues.
Australian Prime Minister Tony Abbott warned that "we cannot be certain of ultimate success in the search" for the Malaysian aircraft. He described it as the most difficult search "in human history."
Authorities have yet to explain why the plane flew off course or where it ended up.
Investigations into the 227 passengers and 12 crew members have yielded no suggestion that any of them might have been behind the disappearance.
CNN's Ben Brumfield, Pam Brown and Elizabeth Joseph contributed to this report.