WASHINGTON — A drug raid on a Los Alamos scientist’s home in New Mexico turned up what appeared to be classified documents taken from the nuclear weapons lab, the FBI said yesterday.

Police discovered the documents at the scientist’s home while making an arrest in a methamphetamine investigation, according to an FBI official in Washington who spoke on condition of anonymity because of the sensitive nature of the case. The police alerted the FBI to the documents, prompting a federal search of the unidentified female scientist’s home. The official would not describe the documents except to say that they appeared to contain classified material. Asked about the raid, FBI special agent Bill Elwell in Albuquerque, N.M., confirmed that a search warrant was executed on Friday night, but he refused to discuss details.

“We do have an investigation with regard to the matter, but our standard is we do not discuss pending investigations,” Mr. Elwell said. A spokesman for the Los Alamos National Laboratory, in Los Alamos, N.M., declined to comment.

Los Alamos has a history of high-profile security problems in the past decade, with the most notable being the case of nuclear scientist Wen Ho Lee. After years of accusations, Mr. Lee pleaded guilty in a plea bargain to one count of mishandling nuclear secrets at the lab.

In 2004, the lab was essentially shut down after an inventory showed that two computer disks containing nuclear secrets were missing. A year later, the lab concluded that it was just a mistake and that the disks never existed.

But the incident highlighted sloppy inventory control and security failures at the nuclear weapons lab. And the Energy Department began moving toward a five-year program to create a so-called diskless environment at Los Alamos to prevent any classified material being carried outside the lab. Even though Los Alamos is now under new management, the executive director of the watchdog group Project on Government Oversight, Danielle Brian, said the lab has not done much to clean up its act.