A Qantas jetliner made an emergency landing Thursday in Singapore with 459 people aboard, after one of its four engines shut down over western Indonesia and following witness reports of a blast that sent debris hurtling to the ground. The airliner denied there had been any explosion, and said the plane landed safely with no injuries. Qantas had no immediate comment on whether the engine troubles were related to eruptions of Indonesias Mount Merapi over the past 10 days. Given the timing of the malfunction, 15 minutes after takeoff from Singapore, and the airliners flight path, there appeared to be no connection. A Qantas statement said the double-decker A380 plane experienced an ''engine issue soon after taking off from Singapore for Sydney. It made a safe emergency landing in Singapore at 11:45 am local time with 433 passengers and 26 crew on board, the statement said. ''Some media reports suggested the aircraft had crashed. These reports are incorrect. No Qantas aircraft has crashed, it said. Qantas spokeswoman Emma Kearns in Sydney, Australia, said there were no reports of injuries or an explosion on board. When asked if the engine trouble was related to ash hurled from Merapi, Kearns said she had no further details. A series of powerful eruptions from Indonesias most volatile volcano, which was spewing massive clouds of gray ash 850 miles west of Batam, earlier prompted officials to close some air routes above the mountain. ''We have no way of knowing what at this point caused the problem, said Tatang Kurniadi, the chief of The National Transportation Safety Committee, when asked if there were fears volcanic ash clogged the Qantas airliners engine. Witnesses on the western Indonesian island of Batam, near Singapore, reported hearing a large blast and seeing pieces of debris including panels painted white and red falling onto houses and a nearby shopping mall. Pictures of metal, some the size of a door, were shown on Indonesias MetroTV broadcaster, with people milling around. ''I heard a big explosion at around 9:15 am and saw a commercial passenger plane flying low in the distance with smoke on one of its wings, Rusdi, a local resident, told MetroTV. ''The debris started falling on my house. A British Airways flight suffered engine failure in 1982 after it had flown into a volcanic cloud in western Sumatra and was forced to make an emergency landing at Jakarta.