PERTH, Australia (AP) —Australian Prime Minister Tony Abbott says crews hunting for Malaysia Airlines Flight 370 have zeroed in on a more targeted area in the Indian Ocean in their search for the source of sounds they believe could be coming from the plane's black boxes.

Abbott says search crews are getting into the stage where signals coming from the flight data and cockpit voice recorders are starting to fade.

But Abbott says "we are very confident" the signals are coming from Flight 370's black boxes.