The U.S. Embassy warned Americans on Monday of a heightened terrorist threat against Westerners in Sudan.

"The U.S. Embassy advises all U.S. citizens in Sudan that the United Nations mission in Sudan has received new information that an extremist group based in the country is likely to target Western interests," it said.

The U.S. message followed a similar warning that the United Nations sent its staff in Sudan last week, said a U.N. official, who spoke on condition of anonymity because he was not authorized to discuss the issue with journalists.

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The U.S. message warned of the danger of bombings, kidnappings and assassinations. It said the primary target of the threat might be the United Nations, but added that "terrorists do not distinguish between official and civilian targets."

U.S. Embassy spokesman Joel Maybury said the warning was standard procedure when a threat was perceived. "In places like Sudan, where you have instability and conflict, we may have half a dozen such messages a year," he said.

Maybury noted there is anger among some Sudanese against the U.N. mission in Sudan, which is promoting the peace process in the south of the country as well as running humanitarian operations in the conflict-ridden region of Darfur in western Sudan.

The United Nations says it has 10,000 peacekeepers in southern Sudan and about 2,500 civilian staff in the whole country. About 1,000 civilian personnel are based in Khartoum.

A U.N. official, who also insisted on not being quoted by name, said the warning stemmed from the tense situation in Darfur, where ethnic fighting has escalated in recent months and U.N. leaders have pressured Sudan's government to allow in a big U.N. peacekeeping force.

The government rejected that demand, but appears to be edging toward permitting small numbers of U.N. forces to deploy in Darfur as part of an 8,000-man African Union peacekeeping mission in the region.

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