Authorities would not say why they returned Friday to the country estate, which they last raided on Nov. 18, 2003, two days before Jackson was booked on molestation charges. The search came just weeks before the scheduled Jan. 31 start date for Jackson’s trial.

The search was conducted “as part of an ongoing criminal investigation,” the Santa Barbara County Sheriff’s Department said in a statement. Spokesman Sgt. Chris Pappas said investigators entered Neverland at 9 a.m. They were seen leaving soon after 5 p.m.

Reached by phone, Jackson attorney Thomas Mesereau Jr. refused comment. District attorney’s spokeswoman Susan Tellem would say only that the warrant was authorized by the court.

Those on both sides of the case are barred from commenting by a court gag order.

Jackson, 46, was leaving Neverland when the officers arrived, and did not stay around, said a source close to the entertainer’s family, who spoke on condition of anonymity.

Activity on the estate was not visible from the road outside. A sheriff’s patrol car was parked inside Neverland’s wooden gates.

A new search so late in the proceedings is very unusual, said a former federal prosecutor who has been following the Jackson case.

“It may mean that the witnesses they are preparing for trial now are remembering things at the ranch that they did not mention before,” said Laurie Levenson, a professor at Loyola Law School. “They may want to follow up on how certain things looked.”

However, she said the search could also be a response to a dispute that has been going on between the prosecution and defense over the legal process known as discovery. The defense has been resisting turning over material to the prosecution, according to documents in the case.

If the search yields any physical evidence it could be of dubious value, Levenson said.

“At this stage, if they found anything, if I were Jackson’s folks I’d say it was planted. So I’m not so convinced how valuable this would be,” she said.

The late-stage search could bolster defense requests to delay the case, Levenson suggested.

“How do you go to trial in a case when they are still serving search warrants?” she said.

Neverland, set amid rolling hills and horse ranches on the edge of Los Padres National Forest about 100 miles northwest of Los Angeles, has a mansion, zoo and amusement park with bumper cars, a merry-go-round and Ferris wheel. Jackson has opened the residence many times to fans and disadvantaged children.

Jackson was originally charged in December 2003 on allegations of molesting a boy. Prosecutors then took the case to the grand jury, which issued a superseding indictment in April.

The pop star has pleaded not guilty to child molestation, conspiracy and administering an intoxicating agent, alcohol, to the alleged victim.