SEOUL, Jan. 10 (Yonhap) – The assailant who stabbed opposition leader Lee Jae-myung in the neck last week has told police that he carried out the knife attack to prevent Lee from becoming president, officials said Wednesday.

The Busan Metropolitan Police Agency announced the finding as it referred the 67-year-old suspect, identified only by his family name Kim, to the prosecution for further investigation and indictment on charges of attempted murder.

"The suspect has said to the effect that he decided to kill the victim so as to prevent him from becoming president and ... taking a majority of seats in the upcoming general elections," said Woo Chul-moon, head of the Busan Metropolitan Police Agency.

He also held a grudge that Lee was not properly punished amid delays in corruption trials, Woo said.

Kim stabbed Lee, the chairman of the main opposition Democratic Party, in the neck in Busan on Jan. 2. He was immediately arrested at the scene, while Lee was airlifted to Seoul and underwent blood vessel reconstruction surgery.

Lee was discharged from the hospital earlier Wednesday and will continue medical treatment at home.

Earlier in the day, Kim appeared before reporters as he was transferred to a prosecutors' office and said: "I caused concerns. I am sorry."

He also claimed to have acted alone without an accomplice, saying, "Who would I have planned this with?"

In an "excuse note" Kim wrote ahead of his crime, he reportedly vented resentment toward politicians and lamented the country's political and economic circumstances.

The police had earlier decided not to disclose his political party affiliation, citing the Political Parties Act, which prohibits an investigative organization from revealing such information obtained during the investigation process.

The police also decided not to make his identity, such as his name and a portrait photo, public, saying that his case did not meet the legal conditions for disclosure. The current law permits the disclosure of the identity of suspects in violent crimes when there is sufficient evidence backing the crime, to meet public interest and people's right to know.

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