Indonesian investigators arrived in central Java late Wednesday to begin a probe into the cause of a jetliner that burst into flames upon landing earlier in the day in central Java.
Meanwhile, reports varied widely on the number of people who died from the fire aboard the Garuda Airlines passenger jet. The fire began as it landed Wednesday morning local time at Yogyakarta airport in central Java.
Bambang Priyogi, the acting spokesman for Yogyakarta Governor and Sultan Hamengku Buwono X, said 21 bodies have been recovered. Provincial Secretary Bamban Susanto told Reuters that 49 people had died.
The Boeing 737-400 was carrying 140 people, according to Garuda Airlines; 133 passengers and seven crew members.
The jetliner was flying from Jakarta to Yogyakarta airport, about 300 miles (482 kilometers) east-southeast of the capital, when the incident took place.
The plane appeared to overshoot the runway, and eyewitnesses reported seeing flames shoot out and hearing an explosion, according to media reports.
Among the passengers were nine Australian government officials and members of the Australian media, and four have not been accounted for, Australian Foreign Minister Alexander Downer said.
"We will always remain hopeful and remain optimistic but with four missing we're concerned about them," he said.
Dismissing concerns that the cause of the crash was "sabotage," Downer said it appeared to be "just a straight accident where the aircraft ran off the runway."
Investigators for Indonesia's National Transportation Safety Board arrived in Yogyakarta Wednesday and will investigate the plane's condition, review the weather pattern and speak with crew members in an effort to find out what caused the plane to erupt in flames, CNN's Kathy Quiano in Jakarta reported.
"We have to wait until the complete investigation is done" before determining the cause, said Andi Mallarangeng, a spokesman for President Susilo Bambang Yudhoyono.
Australian Prime Minister John Howard said he has spoken with Downer and approved emergency aid for the injured.
"We're sending up a defense force medical team that should arrive early tomorrow sometime and an emergency assistance team that will arrive some time tonight," Downer told CNN Wednesday shortly before boarding a plane from Jakarta to the crash site.
He said he planned to investigate the jet himself and visit hospitalized survivors later in the day.
Downer was in Indonesia for four days to host a ministerial meeting on counterterrorism in Jakarta with his Indonesian counterpart, Hassan Wirajuda, this week, according to a March 1 statement issued by him. He was scheduled to depart on Wednesday, and members of the media that were covering the event were among those on the ill-fated flight.
Downer and Attorney General Philip Ruddock were traveling on a Royal Australian Air Force plane instead.
Ninety-three people were evacuated from the Garuda Airlines flight and taken to local hospitals, the airline told CNN.
A Yogyakarta hospital reported receiving 24 to 25 people from the incident but did not elaborate.
Survivor: People in the front last to get out
One survivor said she saw flames outside her window after the plane hit the ground and stopped suddenly. "Things started to fall down [from the overhead bins] ... the smoke started to get in the plane. People were really panicked," Ruth Bamggadan told CNN.
But the emergency door opened, and "quite a lot of people were able to get out of the plane," she said, calling the evacuation fairly orderly with passengers helping elderly women.
People sitting in the front of the plane were the last to get out, Bamggadan said, adding, "I think the emergency door was in the middle."
The front section, or business class, was where staff from the Australian Embassy in Jakarta and members of the Australian federal police and the Royal Air Force were seated, according to Australian government sources. Employees of the Sydney Morning Herald and a television crew from 7 Network were sitting in the back of the plane and reported seeing a number of fatalities, the sources said.
Sources in the Australian Department of Foreign Affairs in Canberra told CNN that Downer and Attorney General Philip Ruddock were traveling on a Royal Australian Air Force plane and were not on the Garuda Airlines flight.
Video footage from the scene showed rescue workers and onlookers surrounding the plane's smoking fuselage. The top of the plane appeared to have burned away.
The plane was about 8-9 years old, according to a Garuda Airlines spokesman.
Indonesia has suffered from a string of transportation accidents in recent months, including an Adam Air plane that disappeared in January with more than 100 passengers and crew on board, and a ferry sinking in late December in which hundreds died.
The plane accident Tuesday occurred one day after a 6.3-magnitude earthquake hit western Indonesia, killing dozens and injuring hundreds more.