This database also contains all the unclassified materials from Energy Research Abstracts.

Machine C was used by bomb designers when they needed to use both classified and unclassified materials.

When they were finished, the designers were required to return the classified and unclassified materials to their respective systems, investigators said.

This collection is a combination of both classified and unclassified material.

Another retiree agreed, saying he believed the agency had begun pressing authors to excise some unclassified material from manuscripts.

The documents include unclassified materials seized by Israeli forces from Palestinian organizations in the West Bank.

Both classified and unclassified materials could be transmitted, decreasing necessary trips back to Washington.

But he said enough unclassified material was available so Mr. Liman could begin work immediately.

They fear that foreign citizens might harm national security by extracting valuable scientific and technical information from the huge volume of unclassified material accessible in computers.

Still, Mr. Lee had access to both classified and unclassified materials in his new job, officials now say.