Japan's transport safety authorities are preparing to investigate an incident at Tokyo's Haneda Airport in which an aircraft crossed a runway just before another airliner landed.
A Skymark airplane arriving from Kobe, western Japan, was approaching a runway on Saturday evening when an All Nippon Airways plane was found taxiing across the same runway.
The transport ministry says an air traffic controller gave both jets permission for their moves.
The planes were reportedly about eight kilometers away from each other, with the Skymark jet flying at an altitude of some 300 meters.
The Skymark plane touched down about three minutes after the ANA jet finished its crossing.
There are no reports of injuries on either plane.
The government's Transport Safety Board is to start an investigation on Monday, saying the incident could have led to a serious accident.