U.S. had signs of impending attacks

SAN'A, Yemen (CNN) -- There had been signs of impending attacks coming from the Middle East when U.S. Secretary of State Colin Powell took office this year, and one of the first briefings he requested was on counter-terrorism, a U.S. official in the Middle East said Wednesday.

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"We had anticipated attacks ... if you look back over the last year, there were ever-increasing warnings," the official said.

"Yes, we knew something was happening," he added. "No, we didn't know it was Manhattan," referring to the September 11 attacks that destroyed the World Trade Center.

The officials believed attacks against U.S. interests were more likely to take place in Europe or the Middle East. As a result, the attacks in New York and Washington came as a surprise, "not strategically, but tactically."

Now, the official said, "Afghanistan is far and away the most important" element of suspected terrorist Osama bin Laden's network. President Bush has blamed the Islamic militant and his followers for the U.S. attacks.

The United States also is examining Afghanistan's "links into Pakistan and the way Pakistan works as a door," the official said. Sudan "used to be significant, but we've been doing very good investigative work there."

The official said the U.S. also is looking carefully at Frankfurt and other European cities, including London, as possible places where terrorists might have ties. U.S. officials also are focusing more intensely on the United States, where the terrorists lived before the September attacks.