Three former executives of a Japanese utility company have been formally charged for alleged negligence in the Fukushima nuclear disaster, becoming the first people from the company to go to criminal court.

National broadcaster NHK reported on Monday that the former Tokyo Electric Power (Tepco) chairman Tsunehisa Katsumata, 75, his vice presidents Sakae Muto, 65, and Ichiro Takekuro, 69, were charged with professional negligence resulting in deaths and injury.

The three men were not taken into custody.

Three reactors at the Fukushima Dai-ichi plant damaged in the March 2011 earthquake and tsunami suffered meltdowns, triggering massive radiation leaks that forced tens of thousands of people to evacuate.

While the earthquake and tsunami killed nearly 18,000 people, no one is officially recorded as having died as a direct result of the nuclear catastrophe.

Marking five years since Japan's tsunami

The charges follow a decision by an 11-member judicial committee in July to send the men to criminal court after prosecutors dropped the case.

Legal analysts say that it may be difficult to prove criminal responsibility for failing to prevent the Fukushima meltdowns, but many people - including residents affected by the disaster - say they hope any trial would reveal more facts.

Government and parliamentary investigative reports have said that Tepco's lack of a safety culture and weak risk management, including an underestimate of tsunami threats, led to the disaster.

They said Tepco ignored tsunami safety measures and was lax in safety oversight.

Tepco has said it could have been more proactive on safety measures, but a tsunami of the magnitude that crippled the plant could not be anticipated.

While struggling with a cleanup at the wrecked Fukushima plant that will take decades, Tepco is hoping to restart two reactors at the Kashiwazaki-Kariwa plant in northern Japan.

The disaster resulted in Japan taking all of its nuclear power reactors offline for checks. Of the 43 workable reactors in Japan, three have been put back online since last year, while the remaining are still offline for repairs or safety checks.

Source: AP And AFP