The prosecution is speeding up its investigation into ex-president Chun Doo-hwan’s hidden assets by formally detaining his brother-in-law over his alleged role in helping Chun’s children illegally gain their inheritance.

The Seoul Central District Court approved the prosecution’s request for an arrest warrant against Lee Chang-seok on Monday evening, saying the suspect may attempt to “destroy evidence or flee.” The 62-year-old was put under detention immediately. By putting Lee, who is thought to be Chun’s “slush fund manager,” behind bars the prosecution is likely to press Chun and his family even more.

The prosecution sought an arrest warrant against Lee on charges of evading 12.4 billion won in taxes while making a shady business deal with Chun’s second son Jae-yong. In 2006, Lee sold part of his property in Osan, Gyeonggi Province to his nephew for 2.8 billion won, substantially lower than the market price of about 50 billion won.

Chun’s children including Jae-yong will likely face the prosecution’s summon soon. The prosecution has also seized Jae-yong’s property in Osan, which he claims to have bought from his uncle, indicating that authorities have obtained evidence to prove the wrongdoings while trading the piece of land.

The prosecution is looking into allegations that Lee’s property in Osan, in fact, belongs to Chun although Lee claimed that the land was inherited by his own father. According to reports, Lee has owned the property since 1984, when Chun was in power.

Not only Jae-yong, Chun’s eldest son Jae-kook is also suspected of laundering his father’s slush funds through an account opened under the name of a paper company he established in the British Virgin Islands.

Chun’s third son Jae-man is no exception. The prosecution has been looking into allegations that he bought residences and businesses in the United States with his father’s concealed assets.

By Cho Chung-un (christory@heraldcorp.com)