A former vice president of Tokyo Electric Power Company Holdings Inc. denied Tuesday his responsibility in the 2011 Fukushima nuclear crisis, saying he did not procrastinate on taking measures against tsunami waves that flooded the nuclear power plant and caused fuel meltdowns.

In a hearing at the Tokyo District Court, Sakae Muto, 68, said he believes it was "an appropriate procedure" to reexamine a 2008 estimate of high waves made by the operator of the Fukushima Daiichi plant, citing the low credibility of the original data used for the projection.

(From left to right, Sakae Muto, Tsunehisa Katsumata and Ichiro Takekuro)

"I had no intention to buy time and I'm offended by the claim that I put off taking measures," said Muto, who is charged with professional negligence resulting in deaths and injuries in connection with one of the world's worst nuclear crises.

Along with Muto, another former vice president Ichiro Takekuro, 72, and former chairman Tsunehisa Katsumata, 78, were also indicted in 2016 for allegedly failing to take measures to prevent the disaster.

The indictment of the three was mandated in 2015 by an independent panel of citizens after prosecutors decided against laying charges.

Earlier testimonies have revealed Muto was informed in 2008 of an estimate that a tsunami as high as 15.7 meters could hit the plant, but asked an engineering association to check how credible the projection was rather than immediately implementing preventive steps.

Muto told the court he thought the projected tsunami "very high" and that it came "out of the blue." The estimate based on the national long-term quake risk evaluation in 2002 was first presented to TEPCO in March 2008 by a subsidiary firm and Muto said he was briefed on that data in June that year.

He defended his move, saying, "I had no decision-making power. We were discussing how to collect information necessary for the company to formulate a policy."

"I thought the long-term evaluation was unreliable," he said, "I was not in a situation where I could decide on measures based on it."

The former executive also said he told Takekuro about the projection of the high tsunami in August 2008, although a lawyer for Takekuro said at the first hearing of the trial in June last year he has no memory of being briefed on it.

Muto offered his apology to those affected by the crisis at the outset of the court hearing, saying, "As a person involved, I deeply apologize to those who died and their families as well as those who had to evacuate."

The prosecution alleges Muto continued to operate the Fukushima plant without taking proper safety measures, while the defense argued the tsunami was unforeseeable as the state evaluation was not credible and the crisis could not have been avoided even if he had taken measures.

Public attention has been on whether the utility was able to foresee a massive tsunami and prevent the nuclear crisis. More than 300 people lined up for the 58 gallery seats at the facility's largest courtroom to listen to Muto's testimonies.

"He didn't come across as someone connected to the company that caused the disaster," said Toshiko Yamada, an evacuee from the city of Minamisoma, Fukushima Prefecture, who now lives near Tokyo.

"It's just terrifying to think such a person was dealing with the nuclear power plant," the 77-year-old said.

The three former executives are blamed for injuries to 13 people, including Self-Defense Forces members, resulting from hydrogen explosions at the plant, as well as the deaths of 44 people, including patients forced to evacuate from a hospital.

Takekuro and Katsunuma are scheduled to be questioned in court later in the month.

On March 11, 2011, the six-reactor plant located on the Pacific coast was flooded by tsunami waves triggered by a major earthquake, causing the reactor cooling systems to lose their power supply. The Nos. 1 to 3 reactors subsequently suffered fuel meltdowns, while hydrogen explosions damaged the buildings housing the No. 1, 3 and 4 units.

Following the crisis, that equaled the severity of the 1986 Chernobyl accident, some 160,000 people were at one stage evacuated and more than 40,000 of them remained displaced as of late September.

Experts and TEPCO officials are divided over the credibility of the evaluation, which covered a massive tsunami that could hit the Pacific shore, including that of Fukushima Prefecture.

Makoto Takao, a TEPCO employee who was in charge of compiling the estimate, has said many seismologists supported the evaluation given by state authorities.

But Tohoku University professor Fumihiko Imamura, who was consulted by TEPCO over the long-term evaluation, said it was something that could not be ignored but it did not prompt immediate action.