Searchers hear signals in Java Sea, but unclear if they are coming from AirAsia's black boxes

Indonesian navy personnel check a helicopter as they prepare operations to lift the tail of AirAsia Flight 8501 in Java sea, Indonesia Friday, Jan. 9, 2015. Days after sonar detected apparent wreckage, an unmanned underwater vehicle showed the plane's tail, lying upside down and partially buried in the ocean floor. (AP Photo/Adek Berry, Pool) (The Associated Press)

PANGKALAN BUN, Indonesia – An Indonesian official says ping-like sounds were heard in an area where searchers are scouring the Java Sea for the crashed AirAsia plane.

Search operations director Suryadi B. Supriyadi says the signals were picked up intermittently Friday, but it's unclear if they came from the cockpit voice and flight data recorders since no pieces of metal were detected nearby. A day earlier, part of the plane's tail was photographed on the ocean's floor — the first confirmed major wreckage from the plane since Flight 8501 went down Dec. 28.

The black boxes are located in the rear of the plane, but Supriyadi said the sounds were heard about one kilometer (half a mile) from the tail's location.

Transportation safety investigator Nurcahyo Utomo said the signals could not be confirmed.