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INCHEON, May 12 (Yonhap) -- Prosecutors said Monday they sought a court warrant to detain the eldest son of the de facto owner of a sunken ferry for disobeying prosecution summons.
Yoo Dae-kyun is the first son of Yoo Byeong-eun, who is suspected to be the owner of Chonghaejin Marine Co., which operated the ferry Sewol that sank off the southwest coast last month.
The younger Yoo was earlier notified to appear at Incheon District Prosecutors' Office in the western port city of Incheon by 10 a.m. Monday.
Judging that the younger Yoo may flee, the prosecution office asked a district court to issue the warrant to detain him for questioning.
The move comes as prosecutors have expanded their investigation into corruption allegations surrounding the Yoo family, who are facing a host of corruption charges, including embezzlement, dereliction of duty, tax evasion and bribery, prosecutors said.
The prosecution office suspects that the elder Yoo -- a businessman, artist, ex-convict and religious figure -- controls Chonghaejin Marine through two of his sons, who own stakes in the firm through various subsidiaries.
The younger Yoo is the biggest shareholder of four affiliates, including I-One-I Holdings, which is Chonghaejin's parent company, prosecutors said.
Prosecutors have already sought arrest warrants for Yoo's second son, Hyuk-ki, and eldest daughter, Som-na, both currently staying abroad, as they have repeatedly refused to respond to prosecution summonses.
Also, the prosecution office called in Kim Han-sik, chief executive of Chonghaejin Marine and one of the closest aides to the elder Yoo, from a prison for further questioning over various graft allegations surrounding the owner family.
Kim was arrested last week on charges of manslaughter and a violation of the vessel safety act.
The 6,825-ton Sewol carrying an estimated 476 people sank off the country's southwest coast on April 16. A total of 275 passengers have been found dead, and 29 others remain missing.
Related to the sinking, prosecutors have sought arrest warrants for two men accused of having failed to properly check emergency chutes that were last assessed in February.
Investigators said the head of a marine safety company, identified only by his family name of Song, and his senior executive, surnamed Cho, had allowed the Sewol ferry receive passing marks and reported the doctored findings to Korean Register of Shipping.
The Gwangju district court also issued a warrant for the arrest of a 37-year-old inspector who assessed the safety of the doomed ship and allowed it to sail. Of the 46 life rafts onboard, only one actually deployed.
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