31.   The number of airplanes, vehicles and people on runways continues to grow, and the head of the National Transportation Safety Board says a catastrophic accident could result.

32.   The Russians have said they suspect the accident resulted from a collision with a foreign submarine, although no definitive cause has been identified.

33.   While immediate concerns focused on the crew, there was also worry over whether the accident would result in a leak of radioactive material.

34.   According to initial investigations, the accident resulted from the driver falling asleep at the wheel.

35.   An official probe later concluded that the accident resulted from a series of pilot errors and mistakes in judgment by US Air Force commanders based in Europe.

36.   CASC officials were unable to say immediately whether the latest accident resulted in casualties.