NAIROBI, March 6 (Xinhua) -- The United States warned its citizens on Tuesday of a possible terrorist attack targeting the upcoming World Cross Country Championships to be staged in the coastal city of Mombasa later this month.

    A statement from the US Embassy in Nairobi said that "unspecified terrorist attack" threat was coming from "alleged extremist elements" and was targeting the IAAF athletics championships due to begin in Mombasa on March 24.

    The alert warned Americans to "use extreme caution" when frequenting prominent places in Mombasa and elsewhere.

    "The U.S. Embassy is also aware of public statements by leaders of Kenya's Coastal Muslim community threatening to disrupt, through unspecified means, the World Cross-Country Championship if the Government of Kenya does not satisfy various demands," Washington said in the statement.

    The warning follows last month's ultimatum by Kenyan Muslims to disrupt the forthcoming World Cross Country Championships unless the government releases their colleagues held unjustly on suspicion of terrorism.

    The Muslims who held a peaceful demonstration on Feb. 20 in Mombasa issued an ultimatum to the government to release 23 Muslims held on suspicion of engaging in terrorism and those detained in Somalia and Ethiopia by March 23 otherwise they would disrupt the international event.

    Their leader Sheikh Mohammed Dor said the Muslims would hold the "mother of all demonstrations" and paralyze business on March 24 should the government fail to meet their demands.

    Last month, Washington issued an alert cautioning its citizens to think carefully before visiting Kenya because of an upsurge in violent crime in the east African country.

    Kenya's Muslims have long complained of being marginalized by authorities, and feel they have been unfairly targeted, particularly since 1998 and 2002 attacks blamed on al-Qaeda-linkedmilitants.