PERTH - The Malaysian frigate KD Lekiu departed Thursday evening from Royal Australian Navy's primary base in the west coast with HMAS Stirling to become another ship enrolled in search operations in Southern Indian Ocean as whereabouts of the missing Malaysia Airlines flight MH370 remained a mystery.

The Malaysian frigate will provide an additional helicopter to assist with the international joint operations and will search the waters for possible debris of the Beoing 777 plane in an area 1,700 km west of Perth. The ship's crew has been briefed on search efforts after 72 hours in port for preparation for resupply.

Commander of Australia-led Joint Task Force 658, Commodore Peter Leavy, said the Malaysian maritime contribution was a welcome addition to the country's two aircraft that have been conducting search operations from RAAF Base Pearce, according to press release by Australian Department of Defense (DOD).

"The contribution of the Malaysian ship's crew will bring further resources to the difficult task of searching for evidence of the fate of flight MH370," Commodore Leavy said.

"The coalition of aircraft and surface vessels will continue to scour the large search area until we are assured there is little chance that physical evidence will be found. Until then, we will assign as many resources as can be safely coordinated," he said.

The KD Lekiu and its helicopter will bring the complement of vessels that are either currently operating in or have been assigned search duties to 14, including HMS Tireless, the Royal Navy submarine.

The Malaysian ship set sail for the search also at a time when Malaysian Prime Minister Najib Razak honored and appreciated tough searching efforts of international air forces at the Pearce Base during his two-day visit to Perth.

"I know it is a daunting task to go out there in very inclement weather, in very challenging circumstances. Malaysia is indeed grateful for your courage and for your commitment," Najib told commanders of seven nations who are here to search for MH370.

Najib said until the plane is found, many families of all 239 people on board can not start to grieve. He promised that Malaysia will not give up.

According to Joint Agency Coordination Center for the joint search efforts, 10 aircraft and nine ships were involved in search activities on Thursday when the search area was adjusted to move north in the southern Indian Ocean. Among them, three aircraft swept the southern search area of 248,000 square km, 1700 km west north west of Perth.

The British Royal Navy hydrographic ship HMS Echo also operated in the northern area searching for sonic transmissions from flight data recorder of the MH370. One alert was experienced but discounted. False alerts may be experienced from biological sources such as whales or interference from shipping noise, the Australian DOD said.

The DOD said there have been no sightings of any objects reported in the day, though weather in the search area was fair, with visibility approximately 10 km.

The Australian Transport Safety Bureau continues to refine the area where the aircraft entered the water based on continuing ground-breaking and multi-disciplinary technical analysis of satellite communication and aircraft performance, passed from the international air crash investigative team comprising analysts from Malaysia, the United States, Britain, China and Australia.