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Threat to U.S. Embassy in Yemen tied to al Qaeda

By Elise Labotte and David Ensor
CNN Washington Bureau

WASHINGTON (CNN) -- Security was tightened Monday at the U.S. Embassy in Yemen in response to a specific and credible threat linked to Osama bin Laden's al Qaeda network, a senior State Department official told CNN.

"There are concerns about al Qaeda activities, capabilities, in Yemen," the senior official said.

The embassy in Sanaa, the capital, issued a security announcement Monday warning that officials believe "there's an increased terrorist threat to U.S. interests in Yemen, including the U.S. Embassy."

The embassy also suspended most consular and visa services.

The warning also advised Americans in Yemen to keep a low profile and to exercise "particular caution" at U.S.-affiliated franchises and areas Americans frequent. It also suggested Americans vary their travel routines and avoid large crowds.

A U.S. official told CNN the threat was not time specific, but it was site specific -- made against the embassy and other sites the official declined to name.

"It is believed to be credible," the official said.

The official said the threat was believed to have come from existing al Qaeda cells, but he said it was possible that some al Qaeda members have fled Afghanistan for Yemen and could have contributed to the threat.

The new threat came amid increased cooperation between the United States and Yemen in the war on terrorism. Last month, Yemeni forces trained and equipped by the United States went after a tribal group believed to be harboring members of al Qaeda.

U.S. Assistant Secretary of State for the Near East William Burns is scheduled to visit Yemen on Thursday as part of a tour of Persian Gulf allies for consultations on U.S. counterterrorism efforts.

State Department spokesman Richard Boucher said Monday the United States was tipped off to the threat by Yemeni authorities. Another State Department official told CNN the United States received intelligence from the Yemenis that focused on the embassy.

Shortly after the September 11 attacks, the United States closed its embassy in Yemen over fears that embassies could become targets.

The embassy reopened in early November, although a travel warning for the country remains in effect, as does an authorized departure of all non-emergency U.S. Embassy personnel.

The United States believes al Qaeda was responsible for the October 2000 bombing of the USS Cole in the Yemeni port of Aden.

Boucher said operations at the U.S. Embassy in Sanaa would resume "at the appropriate time."