Ousted president can be held in a cell for up to 20 days while she is probed on multiple charges, including bribery.
A South Korean court has approved a warrant for ousted President Park Geun-hye, who was removed from office earlier this month over corruption allegations - the first democratically elected leader ever arrested in the country.
Live TV footage showed a black sedan carrying Park entering the detention centre near the capital Seoul early on Friday.
The ruling by the Seoul Central District Court came after Park, 65, faced nearly nine hours of questioning over a number of charges, including bribery and abuse of presidential power.
The court’s decision marks yet another humiliating fall for Park - South Korea’s first female president who was elected in 2012 amid a wave of conservative nostalgia for her late dictator father whose 18-year rule is marked by both rapid economic rise and enormous human rights abuses.
In the coming weeks, prosecutors are expected to formally charge her with extortion, bribery, and abuse of power. A bribery conviction alone is punishable by up to life in prison in South Korea.
Park was held at a prosecutors’ office next door while a judge at the court studied the evidence and arguments to decide on whether to issue the arrest warrant.
"The cause and the need for the warrant are recognised as the main charges against her have been verified and as evidence could be destroyed," the judge said later in a statement.
South Korea is to hold an election in May to choose Park’s successor.
The former president can now be held in a jail cell for up to 20 days while she being investigated.
Park is expected to be transferred to a south Seoul detention facility for high-profile suspects. There, she may be given a bigger cell than other inmates, but she would be subject to the same rules on everything from meals to room inspections, according to former prosecution and correctional officials.
Park had her removal from office confirmed by the country’s top court on March 10, ending her executive immunity, and her prosecution has been a key demand of millions of people who took to the streets to protest against her.
She has been accused of colluding with a friend, Choi Soon-sil, and a former presidential aide, both of whom have been on trial, to pressure big businesses to donate to two foundations set up to back her policy initiatives.
Park is also accused of soliciting bribes from the head of the Samsung Group for government favours, including the backing of a merger of two Samsung affiliates in 2015 that was seen to support the succession of control over the country’s largest "chaebol" conglomerate.
The former president has denied any legal wrongdoing. She apologised for putting trust in Choi, but said she only let her edit some of her presidential speeches and provide the president with some "public relations" help.
Al Jazeera’s Yaara Bou Melhem, reporting from Seoul, called the court’s ruling "historic".
"Park is the first democratically elected leader to be detained after being impeached and forced out of office. The court didn’t take their decision lightly. It’s 3:30am now (18:30GMT), and the court hearing ended yesterday evening after a marathon eight hours and 40 minutes hours of arguments about whether this arrest warrant request should be upheld.
"It was the longest hearing ever held for an arrest warrant, and the court eventually ruled in favour of the prosecution, saying the key allegations have been explained and it’s issuing the arrest warrant because there was the potential she could destroy evidence," Melhem said.
Park, daughter of dictator Park Chung-hee, is also said to have ordered aides to leak secret state files to Choi, and to have cracked down on thousands of artists who had voiced criticism of her or her father’s rule from 1961 to 1979.
Park’s father was gunned down by his own intelligence chief in 1979, five years after his wife was killed in an assassination attempt that targeted him. Park Geun-hye served as first lady after her mother’s death.