Sriwijaya Air SJ182, a domestic flight, took off from Jakarta at approximately 1:56 p.m. local time, losing contact with air traffic controllers at 2:40 p.m., according to Indonesian Transportation Ministry spokesperson Adita Irawati.
The flight reportedly disappeared from radar just four minutes after the pilot called in to ascend to an altitude of 29,000 feet.
A ministry spokeswoman said that Soekarno-Hatta International Airport had asked the pilot why the plane was diverting from its expected flight path, heading northwest just seconds before it disappeared.
Fifty passengers and 12 crew members were aboard the flight, all Indonesian nationals, including six additional crew members for a separate trip.
The Indonesian Navy said ships had been sent to the missing aircraft’s location, though authorities did not specify whether there might be survivors.
In an earlier statement, Irawati said a dozen vessels — four of which are warships — were deployed between Lancang and Laki islands to assist.
Sriwijaya Air reported that the Boeing 737-500 airliner had been scheduled for a 90-minute flight from Jakarta to Pontianak, the capital of the Indonesian province of West Kalimantan.
Reuters reported Saturday that Sriwijaya Air’s president director Jefferson Irwin Jauwena told reporters that the plane had been in good shape before it took off.
Boeing, which typically works with investigators in such cases, told Fox News on Saturday that it was gathering information on what happened.
“Our thoughts are with the crew, passengers, and their families,” the Chicago-based company said. “We are in contact with our airline customer and stand ready to support them during this difficult time.”
Because the plane was built in the United States, the U.S. National Safety Transportation Board will also be included in Indonesia’s KNKT agency investigation of the incident.
The Associated Press reported that debris believed to be parts of a plane and clothing were discovered by fishermen Saturday afternoon in the Thousand Islands just north of Jakarta.
The National Search and Rescue Agency’s Bambang Suryo Aji told reporters the items were handed over to the National Transportation Safety Committee for further investigation.
This is not the first time a Boeing 737 has disappeared after taking off from Jakarta.
In October 2018, a Lion Air Boeing 737 MAX 8 jet crashed into the Java Sea, killing all 189 people on board. That crash and another months later in Ethiopia led to the global grounding of the MAX, a new iteration of Boeing’s widely-flown single-aisle aircraft.
U.S. regulators only recently approved the aircraft’s return to commercial flight. The 737-500 is a much older version of the plane, introduced in the 1980s.
Like Lion Air, Sriwijaya Air is one of Indonesia’s low-cost carriers, with flights both to domestic and international destinations. The air group was founded in 2003.
Fox News’ Travis Fedschun and The Associated Press contributed to this report.