A Malaysian official on Saturday asked the world to ''pray hard'' for a clue to help find Flight MH370, while authorities said a robotic submarine was expected to finish searching a patch of the Indian Ocean seabed within a week after so far coming up empty.
As the hunt for the Malaysia Airlines plane hit the six-week mark, the Bluefin 21 unmanned sub began its seventh trip into the depths off the coast of western Australia. Its search area forms a 10-kilometer (6.2-mile) circle around the location of an underwater signal that was believed to have come from the aircraft's black boxes before their batteries died. The sonar scan of the seafloor in that area is expected to be completed in five to seven days, the search center said in an email to The Associated Press.
The U.S. Navy sub has covered around 133 square kilometers (51 square miles) since it began diving into the depths on Monday. The latest data are being analyzed, but nothing has yet been identified.
Malaysian Defense Minister Hishammuddin Hussein told reporters in Kuala Lumpur that the weekend search is crucial.
''The narrowing of the search for today and tomorrow is at a very critical juncture, so I appeal to everybody around the world to pray and pray hard that we find something to work on over the next couple of days,'' he said.
But he added that there were no plans to give up once the Bluefin concludes its work. Instead, he said the scope of the search may be broadened or other assets may be used.
''The search will always continue,'' he said. ''It is just a matter of approach. All efforts will be intensified for the next few days with regards to the underwater search.''
Meanwhile on Saturday, up to 11 aircraft and 12 ships continued to scan the ocean surface for debris from the Boeing 777 that disappeared March 8 en route from Kuala Lumpur to Beijing with 239 people on board.
Radar and satellite data show the plane mysteriously veered far off course for unknown reasons and would have run out of fuel in the remote section of the southern Indian Ocean where the search has been focused. Not one piece of debris has been recovered since the massive hunt began.
The tiresome search, which continues to raise more questions than answers, has tormented the families whose loved ones were aboard Flight 370. About two-thirds