PERTH, Australia (AP) -- Investigators in the hunt for Malaysia Airlines Flight 370 say tests have ruled out that an oil slick near the search area came from the aircraft.
The center coordinating the search says the oil has tested negative for aircraft oil or hydraulic fluid.
The oil was collected earlier this week from a slick about 3.4 miles from the area where equipment picked up underwater sounds consistent with an aircraft black box.
It was hoped that the oil would be evidence that officials are looking in the right place for Flight 370, which vanished March 8 while en route from Kuala Lumpur, Malaysia, to Beijing.
Searchers have yet to find any physical proof that the sounds that led them to the ocean floor where a robotic submarine has been searching were from the ill-fated jet.