TOKYO, Jan. 28 (Xinhua) -- Tomohiro Kato, 27, pleaded guilty to multiple charges of murder and attempted murder at the Tokyo District Court on Thursday, following a homicidal rampage in June 2008, which left seven dead and wounded ten in the Akihabara district of Tokyo.
Kato, in the first hearing of the case, said that he is " certainly the one who committed the crime" although claimed he could not remember some specifics of what happened on the day of the Sunday afternoon attack.
"I'm sorry for the people who died and got injured," said Kato during the first hearing of what is expected to be a lengthy trial due to the number of people giving testimony and Kato's defense council's rejection of some key evidence and notion that Kato's capacity was diminished at the time of the attacks due to work- related stress and frustration.
The prosecution argued in its opening statement that Kato "did not receive decent treatment" at the office where he was employed as a temporary worker and "felt that what he wrote about in a cell- phone website was ignored."
"So he hit on the idea of getting other people to acknowledge his existence by erupting in anger and setting off a major crime."
The prosecution maintained that Kato had warned in advance of his crime on the website along with a number of posts in which he vented his frustration with his workplace.
The prosecution also said Kato was inspired by a fatal indiscriminate stabbing spree that occurred in March 2008 in Ibaraki Prefecture as well as an April 2005 incident in which three people were killed after a truck crashed into a shopping arcade in Sendai, northern Japan.
"It is apparent that he kept those incidents in mind and decided to kill people at random in Akihabara, where he had been a number of times before," the prosecution said.
The focus of the trial is expected to be on a psychiatric examination that found him mentally competent at the time of the crime, although Kato's defense team questioned the findings claiming their client was mentally diminished when he committed the murders.
The prosecution initially indicted Kato on charges of murder and attempted murder based on the mental evaluation result.
Kato stands charged with plowing down five pedestrians, three of whom died, with a truck on a street in Akihabara that had been closed to traffic because it was a Sunday. After getting out of the truck, he fatally stabbed four passersby with a short-bladed knife.
As Kato was indicted on Oct. 10, 2008, before Japan's introduction of the lay judge system, three professional judges are adjudicating his trial.
The Akihabara killing spree drew a lot of public and media attention predominantly because of the heinous and random nature of the attacks, but partly because it occurred in the popular electronics area that attracts Japanese comic and animation fans and is well-known tourist spot for foreigners visiting Japan.