Secret Iranian nuclear paper assessed

Western and U.N. nuclear officials are evaluating a secret Iranian technical document that appears to show that the country’s nuclear scientists are testing a key component used in the detonation of a nuclear warhead, according to intelligence officials and weapons experts familiar with the document.

The document, if authenticated, could rank as one of the strongest pieces of evidence pointing to a clandestine Iranian effort to build nuclear weapons, said former intelligence officials and weapons experts. They were responding to a published report of alleged research by Iran on one of the final stages in the construction of a nuclear device.

Excerpts from the technical paper, first reported on the Times of London website late Sunday, detail a four-year program by Iranian scientists to develop and test a neutron initiator, a device used to trigger a nuclear explosion.

Although the document is undated, the Times of London quoted foreign intelligence officials as saying it was written in 2007, more than four years after U.S. intelligence agencies believe Iran stopped research on a nuclear warhead.

“It looks bad -- there is no doubt about it,” said David Albright, a former inspector with the International Atomic Energy Agency, the U.N. nuclear watchdog, who reviewed the document and other papers for the London newspaper. He said work on a neutron initiator is a “very strong indicator of nuclear work.”

The CIA had no immediate comment on the report. Former U.S. intelligence officials said the document must be evaluated and accurately dated before any conclusions can be drawn.