Britney Spears' recent spate of all-night partying has raised the concern of the Los Angeles Department of Children and Family Services.

The 25-year-old singer - mother to 15-month-old Sean Preston and three-month-old Jayden James - has been partying hard with new pal Paris Hilton since she filed for divorce from Kevin Federline.

On several occasions Britney has checked into hotels rather than go home to her children.

A source told the New York Post newspaper: "The department has been calling Britney trying to set up a meeting with her, so they can check on the kids. The calls started after this recent bout of bizarre public behaviour."

Britney's own family are also said to be concerned about her recent antics.

Her mother Lynne was said to be horrified when her daughter was pictured on four occasions not wearing any underwear.

The source said: "Lynne is very disturbed and has been trying to get a hold of Britney, but she can't. Lynne, Britney's brother Brian and her dad, Jamie, are very upset and are trying to stage an intervention with her manager Larry Rudolph's help."

The Toxic singer has checked into Los Angeles hotels, including the Viceroy, with Paris Hilton on three occasions now, while her sons are at home being cared for by Lynne.

The Los Angeles Department of Children and Family Services visited Britney in April this year after Sean Preston fell from his highchair and hit his head while being looked after by a nanny. It is possible they could carry out a routine follow-up appointment.

A represent for the department declined to comment.