They came to a police hospital here from all over the country, turning over the most personal of belongings of their loved ones — toothbrushes, diplomas, photos — and swabbed their cheeks, providing DNA samples to aid authorities in finding matches Tuesday with the human remains that continue to be recovered from the sea. 

Families of the 189 people aboard Lion Air Flight 610 are likely to spend agonizing days awaiting confirmation that their loved ones died in an unexplained crash in the Java Sea as rescuers continue to search for the plane’s fuselage, its data recorders and more remains.

On Tuesday morning, the chief of the Indonesian armed forces said the search-and-rescue mission had identified the possible location of the jet’s main body, which is likely to hold its black box. 

The Lion Air flight aboard a new Boeing 737 Max 8 took off from Jakarta heading to the mining region of Pangkal Pinang on Monday morning when, just a few minutes into the flight, the flight crew asked to return to the airport.

Radar showed that the aircraft climbed and descended erratically, and that its speed increased dramatically. Then contact with it was lost.

Aviation experts and authorities, including the head of Indonesia’s National Transportation Safety Committee, told The Washington Post that it is too early to offer any theory on the cause of the crash. Lion Air has provided information on the aircraft and its maintenance logs to authorities, the NTSC chairman said. 

Flight records indicate that the same aircraft had flown abnormally just a day before, with unusual variations in altitude and speed while it was climbing after takeoff.

Lion Air Group’s chief executive, Edward Sirait, said Monday that a prior technical problem was resolved “according to procedure” and that engineers had cleared the aircraft to fly. 

Speaking to reporters Tuesday evening, the airline’s director of safety, Daniel Putut Kuncoro Adi, said all the other Boeing 737 Max 8 planes operated by the airline are being inspected.

A team from Boeing is in Indonesia to assist the investigation, he added, and will meet on Tuesday. 

Indonesian officials said that penalties — including grounding Lion Air — are not out of the question but that such action “can’t be judged this early.”

As experts try to determine what could cause a new plane to crash in apparently favorable operating conditions, rescue and recovery workers aided by sonar equipment and underwater drones are searching for the wreckage, which could provide crucial clues to what went wrong. Fifty divers have been deployed to the crash site off the coast near Jakarta and have expanded the radius of the search, which is expected to last at least a week. 

“We hope that by finding the main fuselage, a black box will be found” said Didi Hamzar, the national search-and-rescue agency’s director of preparedness, using a common term applied to the cockpit voice recorder and the flight data recorder. 

On Tuesday, rescuers were recovering belongings of those on board — passports, children’s shoes, identity cards — and officials picked through them to help make identifications. Of those who were aboard the plane, only fragmentary remains have been recovered so far. They are being sent to a police hospital in dozens of body bags, and a forensics team will try to make identifications.

So far, none of the remains have been identified or matched to those who were listed as being aboard the plane. 

“None of what we have received is in the form of a full body,” said Brig. Gen. Arthur Tampi, head of the National Police Medical and Health Center in Jakarta. 

He cautioned that not all human remains will be recovered. A police officer added that the wide scattering of human remains is likely to complicate the DNA identifications. 

The airline is housing relatives of the plane’s passengers and crew members at a nearby hotel and is providing psychological counseling.

At the police hospital Tuesday afternoon, family members filled out stacks of paperwork at the Disaster Victim Identification Unit, providing information including details of special markings or tattoos to aid in identifications.

Officials provided food and drinks for the relatives, many of whom had been waiting at the facility for hours and were growing frustrated over a lack of definitive information about the crash and the recovery process.

One of those awaiting news of a relative was 64-year-old Edi, who, like many Indonesians, uses one name. His recently married niece, Amalia “Ayu” Resky, 27, was on the flight. He had arrived at the hospital around daybreak and went through the motions of filling out the relevant paperwork. 

“If they find Ayu’s body, we’re bringing her back to Palembang. Her mother wants her there,” he said, referring to the capital of South Sumatra, the Indonesian province where she was from. 

He remembered his surprise when his sister, Ayu’s mother, called him. 

“She seldom calls. So I asked, ‘Why are you calling me?’ ” he said. “She said, ‘Did you hear what happened?’ ”

Mahtani reported from Hong Kong. Ainur Rohmah in Jakarta contributed to this report.