Former TEPCO Chairman Tsunehisa Katsumata (79) and former Vice Presidents Ichiro Takekuro (73) and Sakae Muto (69) were accused of negligence in fulfilling their duties that resulted in deaths and injuries.
The nuclear accident, the second-worst in history after the 1986 Chernobyl disaster, took place after a magnitude-9 earthquake and subsequent tsunami on March 11, 2011, which resulted in at least 18,000 people being killed or disappearing, Efe news reported.
The case against the former TEPCO executives was opened to fix their alleged responsibility for the death of 44 people after being evacuated from a hospital near the Fukushima Nuclear Power Plant, and 13 people, including employees of the facility and members of the armed forces, being injured.
The prosecutors had sought a five-year prison sentence for the former executives of the companies for not adopting prior security measures to avoid a catastrophe like the one which occurred, with the possibility having been raised in an internal report in 2008.
However, the Tokyo District Court found the accused not guilty, more than two years after the trial began on June 30, 2017.
The defence argued that the executives could not have anticipated the tsunami, which led to the reactors being submerged under 10 meters of seawater.
Of the six nuclear reactors at the Daiichi facility, four suffered considerable damage, and three witnessed partial meltdowns after the cooling systems were disabled by the earthquake and tsunami, which cut off the power supply to the plant and flooded the reserve electric generator.
( With inputs from IANS )