TOKYO (AP) — Three former executives of Tokyo Electric Power Co. went on trial Friday for alleged negligence in the 2011 Fukushima nuclear disaster.

The trial in Tokyo District Court is the first to consider whether utility officials can be held criminally responsible.

Three reactors had meltdowns, and radiation spread into surrounding communities after the nuclear plant north of Tokyo was hit by a powerful earthquake and tsunami on March 11, 2011. Tens of thousands of residents were forced to evacuate, and some areas remain uninhabitable more than six years later.

The trial is expected to focus on whether the former officials should have been aware of the risk and whether the disaster could have been prevented.

Tsunehisa Katsumata, 77, the chairman of TEPCO at the time, and former vice presidents Sakae Muto, 67 and Ichiro Takekuro, 71, are being tried.

The three men are charged with professional negligence resulting in death and injury, including the deaths of more than 40 senior citizens during and after lengthy evacuations from a hospital, and injuries to 13 people including TEPCO employees during emergency work.

Prosecutors considered the case twice, and dropped it both times, but a citizens' judicial panel overrode their decision and indicted the former executives. They are being tried by a team of lawyers appointed by the court.

The three are accused of not taking sufficient measures despite being aware of the risk of a major tsunami at the Fukushima plant at least two years before it happened. The trial is expected to take more than a year.

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