Pop starlet and troubled tabloid favorite Britney Spears, and her one-year-old son, were taken from her home by paramedics Friday, celebrity website TMZ reported, after police had been called to resolve a custody dispute.
TMZ said Spears had been taken to a hospital for a "medical hold," which it described as a mental evaluation.
Police "found her earlier this evening at her home under the influence of an 'unknown substance'," after being called when she returned her two young sons to their father.
After a three-hour stand-off, TMZ said Spears handed over the children, aged two and one, and was wheeled into an ambulance. Television footage showed a smiling Spears being carried on a gurney.
TMZ reported that the youngest of her children, Jayden James, was also taken away in an ambulance, but gave no further details.
Spears's on-going custody battle with her former husband, Kevin Federline, has been the source of lurid headlines, spiking after a judge limited her access to her children in October.
The drama comes after a difficult year for Spears, who in 2007 spent a month in a rehabilitation hospital, lost custody of her children and was slammed in the media for her partying and erratic behavior. And in December, her 16-year-old actress sister -- a star in her own right -- announced she was pregnant.
She released an album to surprisingly good reviews, but did not tour or promote it.