A former employee of the National Security Agency packed cardboard boxes with secret national security documents and unlawfully took them to his Waldorf home, where he kept them in his kitchen and in a safe in a bedroom closet, a federal prosecutor said in U.S. District Court in Greenbelt yesterday.

Kenneth W. Ford Jr., 34, is on trial on charges that he took national security documents without authorization. Ford is also accused of failing to inform a prospective private-sector employer, who required him to have a security clearance, that he was charged with taking the secret documents illegally.

Ford worked as a computer expert at the NSA, prosecutors said. The contents of the documents he allegedly took remained a mystery yesterday after opening statements by Mariclaire Rourke, a trial attorney with the Justice Department's counterespionage section, and Ford's defense attorney, Spencer M. Hecht.

It was unclear how much, if any, of the documents' contents would be made public during the trial, which is expected to last about two weeks. Prosecutors do not allege that Ford took the documents to give or sell to an enemy of the country.

In his opening statement, Hecht said it would have been impossible for Ford to take home classified documents without the proper authority to do so. "This case is anything but a slam-dunk," he said.

According to prosecutors, Ford was arrested after the FBI received a tip from Tonya Tucker, then a girlfriend of Ford's. Hecht said that there is a connection between Tucker and the NSA and that she, not Ford, should be on trial.

Rourke said in her opening statement that Ford acknowledged to FBI agents that he took the documents home, telling them he wanted to use them as reference points for his new job with Northrop Grumman Corp., a federal government contractor.

"There is no excuse," Rourke said. "You just can't bring home classified documents and leave them in your kitchen."

Ford, a former member of the uniformed division of the Secret Service, worked for the NSA from summer 2001 until early January 2004. On his last day at work there, Ford packed up the cardboard boxes with national security documents, left through an unguarded exit and loaded them into his pickup, Rourke said.

FBI agents went to Ford's home Jan. 11, 2004, after they received a tip from Tucker.

When agents asked Ford whether he had any classified documents, he showed them two cardboard boxes of such documents in his kitchen, including one that contained documents stacked about a foot high, Rourke said.

When investigators asked Ford whether he had any more secret documents, the prosecutor said, he took them to a closet in an upstairs bedroom, where they found more documents in or near an open safe. The agents also found additional documents in a suitcase Ford's former girlfriend had used, a suitcase that bore Ford's fingerprint, Rourke said.

Ford provided a handwritten statement and was arrested, Rourke said.

A few months after the arrest, a federal magistrate judge told Ford during a court hearing that if he applied for any job requiring a security clearance, he must divulge that he was charged with unlawfully possessing national security documents, Rourke said.

Ford subsequently applied for a job with Lockheed Martin Corp., a private firm that contracts with the CIA. Although the job required a security clearance, Ford did not disclose the fact that he was facing the charge of unlawful possession of national security documents, Rourke said.