China said Saturday that one its ships searching for Malaysia Airlines Flight MH370 has detected a radio pulse or "ping" in the southern Indian Ocean - a signal that could have come from the missing jet's flight data recorder.
If confirmed, experts say the monitored signal could be a breakthrough in efforts to solve the mystery surrounding the missing plane and its 239 passengers and crew. China's official Xinhua news agency reported the pulse was heard at 37.5 kilohertz per second - the international standard radio frequency for a flight data recorder's underwater beacon.
Malaysia Airlines' flight from Kuala Lumpur vanished nearly one month ago , during the early stages of a scheduled flight from Kuala Lumpur to Beijing.
The wide-ranging search has focused on a remote area of the southern Indian Ocean, where an underwater hunt began Saturday. The search has become more intense as the batteries in the black boxes are due to reach the end of their life very soon.
Ships using submersible sonar and numerous military and private aircraft were deployed Saturday in a patch of the Indian Ocean about 1,700 kilometers northwest of Perth, Australia. Position information given out by China indicates its search ship was slightly outside the targeted area when it monitored the "ping" signal on Friday.
Flight MH370 vanished without any distress calls, and authorities have refused to rule out any possibilities, including hijacking, sabotage or a mechanical malfunction. Malaysian officials say they are continuing to investigate whether any deliberate action by the pilots or crew could have sent the plane down.