End of the party for Britney

Britney Spears has checked into an undisclosed rehab centre after a bizarre weekend that included shaving her head, according to her manager.

The pop princess checked into the facility voluntarily on Tuesday,LarryRudolph said.

"We ask that the media respect her privacy as well as those of her family and friends at this time," Rudolph was quoted as saying on the People magazine website.

Some celebrity gossip sites reported on Monday that Spears, the mother of two young boys, was under the influence of drugs when she shaved her head and got two new tattoos on Friday.

People magazine also claimed Spears had checked into a rehab centre last week, but checked out after a day.

Since her split from husband Kevin Federline last September, Spears has become known for her partying ways. One of her party companions, actress Lindsay Lohan, is also in rehab.

Spears was seen in Los Angeles nightclubs, with a wig covering her shaved head, this weekend.

Spears, 25, is known for hits such as Baby One More Time.