Transport minister Seiji Maehara blasted the Japan Coast Guard on Friday for what could be taken as a coverup attempt in its handling of Wednesday's helicopter crash in the Seto Inland Sea off Kagawa Prefecture.

The Hiroshima-based 6th Regional Coast Guard Headquarters said Thursday night that the helicopter crash that killed four crew members occurred between demonstration flights it was making for successful bar exam applicants. The fifth crewman aboard the chopper is missing.

Initially, the regional headquarters had only announced that the chopper was on a patrol, failing to reveal the aircraft crashed between two planned demonstration flights. The copter hit and severed power lines.