JAKARTA (Reuters) - Lion Air has ended its search for the cockpit voice recorder (CVR) from its Boeing 737 MAX jet that crashed into the Java Sea in October, but Indonesian investigators said they plan to launch their own probe as soon as possible.

Indonesian customs officers patrol at a search area for Lion Air flight JT610 in Karawang waters, Indonesia, November 1, 2018. REUTERS/Edgar Su

The crash, the world’s first of a Boeing Co 737 MAX jet and the deadliest of 2018, killed all 189 people on board.

Contact with flight JT610 was lost 13 minutes after it took off on Oct. 29 from the capital Jakarta heading north to the tin-mining town of Pangkal Pinang.

The main wreckage and the CVR, one of two so-called black boxes, were not recovered in an initial search. Lion Air said in December it was funding a 38 billion rupiah ($2.64 million) search using the offshore supply ship MPV Everest.

The search using the ship ended on Saturday, Danang Mandala, the spokesman for Lion Air Group, told Reuters.

A spokesman for the National Transportation Safety Commission (KNKT), however, said on Thursday the agency would start its own search for the black box as soon as feasible.

The CVR is likely to hold vital clues that could give investigators insight into the actions of the pilots.

The KNKT spokesman said negotiations with the Indonesian navy were under way to use a navy ship to relaunch the search for the second black box as soon as possible.

“It might be as soon as next week. It won’t be as fancy as the (Lion-subsidized) MPV Everest but will be equipped with a CVR detector and we already have a remote-operated vehicle,” the commission’s spokesman said.

The clock is ticking in the hunt for acoustic pings from the L3 Technologies Inc CVR fitted to the jet. It has a 90-day beacon, the manufacturer’s online brochure shows.

A preliminary report by KNKT focused on airline maintenance and training and the response of a Boeing anti-stall system to a recently replaced sensor but did not give a cause for the crash.

“While we appreciate the fact Lion Air Group brought out the MPV Everest ship, we are disappointed because there’s no actual results,” Anton Sahadi, a relative of a victim of the plane crash, told Reuters by a text message.

“It has been a waste of money, of time and of a sophisticated ship ... for several weeks, we the families of victims were given only fake promises by Lion Air,” he said, adding he was not confident in the government’s efforts.

The family of the Indonesian co-pilot of the flight filed a wrongful death lawsuit on Friday against Boeing in Chicago, adding to litigation piling up against the planemaker. [L1N1YX156]

The lawsuit alleges that the Lion Air-operated Boeing 737 MAX jet was unreasonably dangerous because its sensors provided inconsistent information to both the pilots and the aircraft.

At least two other lawsuits have been filed against Boeing in Chicago by relatives of victims.

There has also been some debate among experts over Indonesian authorities’ decision to ask Lion Air to pay for the search that ended on Saturday.

Safety experts say air accident investigation agencies typically lead the search for black boxes with public funding to ensure the independence of the process and that it is unusual to hand the task to one of the parties to the investigation.

Indonesian investigators previously said that bureaucratic wrangling and funding problems had hampered the search for the Lion Air CVR and they had turned to the airline for help.

In 2007, efforts to recover the black boxes from a crashed Adam Air jet were delayed by disagreements between the Indonesia and the airline over who should bear the cost.