KANCHANABURI, Thailand — Searchers trekked through mountain jungles and scanned the Thai-Burmese border from the air Monday but found no trace of a South Korean jetliner that vanished over Burma with 115 people aboard.
Contradicting earlier reports that the wreckage had been found, officials conceded that they have no idea in which country the aircraft might have crashed or why it disappeared Sunday on a flight from Baghdad, Iraq, to Seoul.
The search, suspended until daybreak today, is to focus on both land and sea.
A flurry of conflicting reports Monday from Thai and South Korean officials added to the confusion surrounding the disappearance of Korean Air Flight 858.
Early Monday, Air Vice Marshal Sommot Sundaravej, spokesman for the Thai air force, said the Boeing jet crashed in Thailand's Kanchanaburi province, along the border.
Later, Col. Punlop Roongsumphun, police chief of Kanchanaburi province, said a helicopter crew spotted the wreckage. The search then concentrated on that area, about 100 miles west of Bangkok.
Finally, Lt. Gen. Chitr Boonyachai of the Kanchanaburi police told reporters: "We did not spot the wreckage or find out anything about the aircraft. Initial police reports were uncertain."
Meanwhile, Korean Air President Cho Choong Kun said the airline's investigation is concentrating on the possibility that a bomb had destroyed the jetliner.
"A bomb may have been planted by terrorists or other impure groups," said Cho, who arrived in Bangkok with a team of investigators and set out for the province.
Most of the plane's passengers were South Korean construction workers returning from jobs in the Middle East.
Airline officials confirmed earlier Monday that the missing plane had a history of technical problems. The plane made two crash landings during the last 10 years, including a belly landing at Seoul's Kimpo airport in September.
During Sunday's flight, the pilot did not report any problems on the last contact he made with air traffic controllers, after entering Burmese air space.