Samsung Group chief Jay Y. Lee was arrested early on 17th Feb 2017 over his alleged role in a corruption scandal rocking the highest levels of power in South Korea.
This is dealing a fresh blow to the world's biggest maker of smartphones and memory chips.
The 48-year-old Lee, scion of the country's richest family, was taken into custody at the Seoul Detention Centre after waiting there overnight for the decision.
He was being held in a single cell with a TV and desk, a jail official said.
Lee is a suspect in the influence-peddling scandal that led parliament to impeach President Park Geun-hye in December.
This decision if upheld by the Constitutional Court would make her the country's first democratically elected leader forced from office.
Shares in flagship Samsung Electronics Co Ltd opened down 1.2 percent+ , while shares in Samsung C&T Corp , the de facto holding company of Samsung Group, opened down 3.2 percent compared with the wider market's drop of 0.45 percent.
Prosecutors have up to 10 days to indict Lee, Samsung's third-generation leader, although they can seek an extension.
After indictment, a court would be required to make a ruling within three months.
Samsung and Lee have denied wrongdoing in the case.
The same court had rejected a request last month to arrest Lee, but prosecutors brought additional accusations against Lee, seeking his arrest on bribery and other charges.
The judge rejected the prosecution's request to arrest Samsung Electronics president Park Sang-jin.
Lee's detention could hinder strategic decision-making by South Korea's biggest conglomerate.
Samsung has been in the midst of an ongoing restructuring to clear a succession path for Lee to assume control after his father was incapacitated by a heart attack in 2014.
Lee's incarceration comes as Samsung Electronics tries to get past the disastrous roll out last year of its Galaxy Note 7 smartphones, which were prone to fires.
It is under pressure for the upcoming launch of its next flagship phone, the Galaxy S8, to be a success.
Prosecutors have focused on Samsung's relationship with Park, 65.
They are accusing the group of paying bribes totalling 43 billion won ($37.74 million) to organizations linked to Choi to secure government backing for the 2015 merger of two Samsung units.
Samsung: Know More- Headquarters: Seoul, South Korea
- Founder: Lee Byung-chul
- Founded: 1 March 1938, Daegu, South Korea
- Owner: Lee Kun-hee
- Revenue: 305 billion USD (2014)
- Number of employees: 489,000
- Subsidiaries: Samsung Electronics Limited
