Three former executives of Tokyo Electric Power Co. were indicted Monday for allegedly failing to take measures to prevent the tsunami-triggered crisis at the Fukushima No. 1 nuclear plant in March 2011.

The indictment, mandated by an independent panel of citizens after prosecutors decided against bringing charges, seeks to answer in court the question of whether the key Tepco figures should be held criminally responsible for the disaster.

The three executives facing charges of professional negligence resulting in death and injury are Tsunehisa Katsumata, 75, chairman of Tepco at the time, and two former vice presidents, Sakae Muto, 65, and Ichiro Takekuro, 69.