American intelligence officials have said they have no information linking those warnings to a specific threat.
Saudi journalists have also been ordered to stop digging for information linking the hijackers to Saudi Arabia.
Mr. Blakey said he had no information linking the discovery of the materials to any threats against the company.
For Vaughan, this was a piece of revelatory information linking Chanel to German intelligence operations.
"We do not have any information linking U.S. persons to the bombing," a State Department official, speaking on condition of anonymity, said today.
That by itself had been interesting enough, but that interview had also revealed information linking, if distantly, to more urgent issues.
"Do you have any new information linking Iraq to terrorism?"
A senior State Department official said earlier this week that the department had been aware of information linking Arrendondo to violent activity.
Prosecutors said they had information linking Mr. Zapata to two other killings, although he has not been charged in those cases.
Another bit of information linking genetic and environmental causes is that researchers have found that too much alpha-synuclein can lead to oxidative damage.