Knight, 49, complained of chest pains in court Tuesday after pleading not guilty to murder charges for allegedly running over two men -- killing one of them -- following an argument.
After being released from the hospital, Knight was taken back into custody by the Los Angeles County Sheriff's Department a little before 9 p.m. Wednesday (midnight ET), Deputy Kelvin Moody told CNN.
"We are not purview to any medical treatment he may be for receiving," said the Sheriff's Department spokesman, who did not specify whether Knight was being held in a normal jail cell or elsewhere.
Mark Blankenship, president of Everlert Entertainment and who has business dealings with Knight, told reporters Tuesday that Knight "has special medicine he needs" that he couldn't access after turning himself in early last Friday, flanked by his lawyer.
The deadly incident happened January 29, after a flare-up on the set of the biopic "Straight Outta Compton," a film about the highly influential and controversial rap group N.W.A. The argument spilled over to the parking lot of Tam's Burgers in Compton.
"It looks like he drove backward and struck the victims," Los Angeles County Sheriff's Lt. John Corina said of Knight. "And then went forward and struck them again as he left."
Officers later found Knight's Ford Raptor abandoned in nearby Westwood.
Latest legal run-in for ex-rap mogul
His attorney, David Kenner, said Knight felt remorseful about the death of former rap record label owner Terry Carter and injuries to Cle "Bone" Sloan, both of whom he considers longtime friends.
"From what I understand ... he was being attacked and trying to get away from that attack, no more than that," Kenner said. "... It's not his fault."
Michael Shapiro -- the attorney for Sloan, 51, who is out of the hospital after suffering a serious concussion and having his left foot mangled -- dismissed that version of events as "absurd."
The incident is the latest run-in with the law for Knight, who founded the wildly successful Death Row Records in 1991 and signed artists such as Snoop Doggy Dogg and Tupac Shakur.
Knight was driving the car in which Shakur was a passenger when the rapper was shot to death in Las Vegas in 1996.
Shortly afterward, Knight spent several years in prison for violating parole on assault and weapons convictions. That prison time -- along with Shakur's death, feuds between Knight and a number of rappers and desertions by Dr. Dre, Snoop and others -- contributed to the label's bankruptcy in 2006.
And in August, Knight and two other people were shot while inside a celebrity-filled Sunset Strip party hosted by singer Chris Brown on the eve of the MTV Video Music Awards.
At the time of his most recent arrest, Knight was free on bail in a robbery case.