Qantas blast is investigated

Australian investigators are exploring the possibility that an oxygen cylinder could have exploded mid-flight on the Qantas jumbo jet that made a harrowing emergency landing in the Philippines with a large hole in its fuselage.

The Boeing 747-400 was cruising at 29,000 feet Friday with 346 passengers aboard when it was shaken by what passengers described as an explosion. Oxygen masks dropped from the ceiling as the plane descended rapidly and debris flew through the cabin from a hole that appeared in the floor.

Boeing spokeswoman Liz Verdier said the design of the Qantas jet includes dozens of oxygen tanks located throughout the lower part of the aircraft, including below the passenger compartment where the hole appeared.