Lee Jae-yong, Samsung's vice chairman and de facto chief, has been arrested by South Korean police after prosecutors claimed to have secured new evidence against him in a long-running bribery and corruption case in which President Park Geun-Hye is also implicated.
He was arrested on Thursday after fresh evidence was produced by prosecutor Park Young-soo, who has been attempting to put together a bribery case against Lee and President Park.
The Seoul Central District Court had previously rejected the prosecutors' request to arrest Lee citing insufficient evidence, however after the presentation of new evidence it has changed its opinion.
"We acknowledge the cause and necessity of the arrest," said Judge Han Jeong-seok .
Mr. Lee, who has not been convicted of any crime, was taken into custody in the Seoul Detention Centre and remained there while the court arrived at its decision in a closed-door hearing which ended on Thursday evening. Prosecutors must now indict him within 20 days. Other charges against Lee include embezzlement, illegal property dealings and perjury.
Samsung has been embroiled in a political scandal which in December led to the impeachment of President Park, after months of political turmoil in South Korea. Park, who has been stripped of her powers, awaits a final decision by the Constitutional Court on whether the impeachment will stand.
The prosecutor is also preparing to bring bribery charges against Ms Park, although she cannot be indicted while she is in office.
During investigations into the political scandal Samsung's offices were raided by the police. Prosecutors allege that the company bribed the government to the tune of 43bn won (£30.2m) via Park's associate Choi Soon-sil, to secure state backing for a 2015 corporate merger. Lee has already admitted funding the equestrian career of Ms Choi's daughter, Chung Yoo-ra, in Denmark.
Last year Lee Jae-yong, who is 48, took over the running of the company from his father Lee Kun-hee, who suffered a heart attack in 2014 but remains leader of the Samsung Group. Lee Kun-hee has also been arrested twice on bribery charges; he was acquitted on both occasions.
In a statement Samsung said: "We will do our best to ensure that the truth is revealed in the court proceedings."
The arrest comes at a bad time for Samsung which is struggling to affect a smooth transfer of power within the Lee dynasty. It had been hoped that Lee Jae-yong's taking over the reins from his father would provide some much needed stability.
There have long been concerns among investors about Samsung's complex structure, with repeated calls that it should be broken up. Samsung's disastrous 2016, with the damage inflicted by the exploding batteries in the flagship Note 7 phablet amounting to billions of dollars, has given the upper hand to investors who say that Samsung should be split into two units: an operational enterprise and holding company.
The South Korean authorities are also investigating an alleged anti-competitive deal between Google and Samsung signed in 2011 that effectively locked out other operating systems apart from Android.
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