ELIEVES THOSE RESPONSIBLE FOR THE ATTACK ARE HIDING. DUE TO CONTINUED CIVIL AND POLITICAL UNREST THROUGHOUT MOST OF THE CAUCASUS REGION OF RUSSIA, THE U.S. DEPARTMENT OF STATE WARNS U.S. CITIZENS AGAINST TRAVEL TO THE AREAS OF CHECHNYA AND ALL AREAS BORDERING CHECHNYA. 10. CUST/IMMIG/AGRIC - A. CREW AND PASSENGERS ARE RE