An appeal has been filed with the Tokyo High Court challenging the acquittal of three former Tepco executives over the 2011 Fukushima nuclear crisis.

"Letting this decision stand is clearly against justice. Taking into consideration the burden of the victims, it is incumbent on us to demand a judgment by a higher court," one of the court-appointed lawyers acting as prosecutors said when the appeal was filed Monday.

They had sought five-year prison sentences for the former executives of what is now called Tokyo Electric Power Company Holdings Inc.