The 26-year-old pop star was taken to Cedars-Sinai Medical Center, "Entertainment Tonight" reported on its Web site Friday. A spokeswoman for the hospital wouldn't confirm or deny the report, citing patient confidentiality.
Police reportedly had to intervene when she refused to return the children to Federline after a court-monitored visit. Officer Jason Lee of the Los Angeles Police Department told a news organization that Spears appeared to be under the influence of an unknown substance.
Spears was conscious when paramedics took her out of her home on a gurney just before 11:00 p.m. The ambulance that took her away was followed by several police cars and dozens of paparazzi.
After the custody ruling late Friday afternoon, Commissioner Scott Gordon ordered another hearing to be held January 14th. Federline had previously been awarded temporary custody of 2-year-old Sean Preston and 1-year-old Jayden James because Spears has defied court orders, resulting in limitations on her visitation.
"I'm not happy about any of these events," Federline attorney Mark Vincent Kaplan said when he left a closed-door emergency hearing Friday afternoon. "There's no winners here."
Federline was not in court for the hearing, Kaplan said. The attorney had said he did not expect the ruling to be released until Monday, but it was issued shortly after the hearing concluded.
Spears and Federline have been involved in a long and very public custody battle. The two were married in October 2004 and divorced in July.
Spears has appeared increasingly out of control during the past year. She has been photographed without underwear and appeared to be drunk and out-of-control. She shaved her head, beat a car with an umbrella and spent a month in rehab and has had a handful of fender benders, including one in which she ran over a photographer's foot.
