While acknowledging that there was "a commonality" in foreseeing the possibility of unspecified new threats, Mr. Putin said, "We're against having a cure which is worse than the disease."

The lone cabin in the woods has long been an American emblem, but it has also always contained an element of unspecified threat.

Most said they were already doing all they could to protect against unspecified threats.

Football (soccer): Swedish referee Anders Frisk announces his retirement with immediate effect, after receiving so-far unspecified threats.

If not..." He let the unspecified threat hang in the air.

Then he dealt his career a near-fatal blow when he closed his Washington office for a month in October 2004, after an unspecified terrorist threat.

An unspecified threat forced Mr. Bush to cancel his appearance today at the offices of Radio Free Europe.

Carefully posed and lighted, scenes of this sort take on a sense of dramatic moment and, often, of unspecified threat.

The USembassy in Sarajevo, a mainly Muslim city, closed briefly in March 2002 citing an unspecified threat, but the building has not come under attack before.

"They explained that the order was the result of concerns about the protection of the American community from unspecified threats," Mr. Boucher said.