The prosecution said Sunday that it has decided not to press charges against President Lee Myung-bak’s son and others accused of irregularities in the process of purchasing Lee’s retirement residence.

Concluding their five-month investigation, officials at the Seoul Central District Prosecutors’ Office said they found no sign of illegality in the purchase of a 2,600-square-meter plot in Naegok-dong, southern Seoul.

None of the seven accused, including Si-hyeong, Lee’s 34-year-old son, and Lim Tae-hee, a former presidential chief of staff, were indicted.

The prosecutors began looking into the presidential transaction in January, following a complaint filed by opposition parties last October.

The main opposition Democratic United Party and far-left Unified Progressive Party said in the complaint that the president and his son had violated laws on the use of real names in property transactions. They also suspected misappropriation of state money.

Of the total 2,600-square-meter plot, Si-hyeong bought 462 square meters of land for 1.12 billion ($954,000) won while the presidential office bought a larger portion of 2,142 square meters for security personnel at a cost of 4.28 billion won. Both purchases were completed in May 2011.

Critics have claimed that such an arrangement caused a loss to the nation’s coffers.

The prosecution, however, said the presidential office paid for the land based on accurate calculations and there has been no intention to cause loss to the nation.

The prosecutors also cleared Si-hyeong of violating the real-name rules.

“(Lee) Si-hyeong borrowed 600 million won from relatives and a bank respectively under his name. He has paid interest.”

The president is exempt from criminal liability during his five-year term, except in the cases of insurrection or treason.

“Cheong Wa-dae respects the result of the investigation. We feel deeply sorry for the concerns,” presidential spokesperson Park Jeong-ha told reporters after the announcement of the prosecutors’ office.

“The portion of the land that the presidential office has is in the sale process, and Lee’s portion will be nationalized following due procedure.”

The prosecutors said they will continue to keep an eye on any mistakes or irregularities made by public officers during the deal.

Stung by public criticism of the deal, President Lee scrapped his plan to live in Naegok-dong after retirement and decided to renovate and live in his existing house in Nonhyeon-dong.

By Kim Young-won (wone0102@heraldcorp.com)