In the search for the plane in the Indian Ocean, a Chinese patrol ship Haixun 01 picked up two signals, one on Friday and another on Saturday, that were only 2 kilometers (1.25 miles) apart, authorities said.
“This is an important and encouraging lead, but one that I urge you to continue to treat carefully,” Angus Houston, the head of the Australian agency coordinating search operations, said Sunday.
The electronic pulses were consistent with those emitted by the pingers on an aircraft’s flight data and voice recorders, he said, but haven’t been verified as coming from Flight 370.
Sounds also travel long distances underwater, he said, making it difficult to ascertain their sources. If detectors were near a pinger, they would pick up the signal for a more sustained period.
Houston also said that search authorities were informed Sunday that Ocean Shield, an Australian naval vessel equipped with sophisticated listening equipment, has detected “an acoustic noise” in another area of the ocean.
The signals are the latest leads in a huge, multinational hunt for Flight 370, which disappeared almost a month ago over Southeast Asia with 239 people on board. Investigators have so far been unable to say why the plane flew far off course or where exactly it ended up.