Spears, 24, married rapper Kevin 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.

Calls left for Federline’s representatives also were not immediately returned.

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.