LOS ANGELES -- Britney Spears is saying bye-bye to K-Fed. The pop princess filed for divorce Tuesday from her husband, former backup dancer and aspiring rapper Kevin Federline. The Los Angeles County Superior Court filing cites "irreconcilable differences," said court spokeswoman Kathy Roberts.

Spears, 24, married Federline, 28, in 2004. They have a 1-year-old son, Sean Preston, and an infant son who was born Sept. 12. The divorce papers identify the baby as Jayden James Federline.

A message left with Spears' attorney, Laura Wasser, was not immediately returned.

Spears married Federline eight months after ending a 55-hour Las Vegas marriage to her childhood friend, Jason Alexander. Her second marriage has provided endless fodder for tabloids, which have speculated frequently that the union was in trouble.

Federline's attorney, Mark Vincent Kaplan, issued a statement declining comment.

"There is no statement at this time as requested by Mark's client, Kevin Federline," said Michael Sands, spokesman for Kaplan.

In the divorce papers, Spears asks for custody of the couple's two children, with visitation rights for Federline. The filing lists as separate property, and thereby off-limits to Federline, "miscellaneous jewelry and other personal affects," earnings and other assets to be determined later.

The filing comes just a day after Spears, back in shape after the birth of her second child, made a surprise appearance on David Letterman's "Late Show" in New York by popping up behind him as he was sitting at his desk.

Federline appeared in the movie "You Got Served" and performed as a backup dancer for singer Justin Timberlake, Spears' former boyfriend. He was previously involved with actress Shar Jackson of TV's "Moesha." Federline and Jackson have two children.

Born in Kentwood, Louisiana in 1981, Spears got her first taste of fame at age 11 when she joined the "New Mickey Mouse Club" TV show.