Ringleader of an armed gang Abu-Muslim Umayev, 30, and his underling Sakhab Vakhayev, 25, were destroyed as a result of a special operation in the district center Achkhoi-Martan, Tass learnt on Monday at the press center of the regional headquarters on the counter-terrorist operation in the North Caucasus. "The gunmen were blockaded at a private house and were destroyed, since they offered an armed resistance," the press service reported.Federals found a great quantity of firearms and ammunition at the place of the clash as well as note-books with reports on terror acts, committed by the gang against civilians, a diskette with religious extremist recordings as well as blanks to make forged ID cards of law enforcers. Federal troops now conduct pinpoint check-ups in Achkhoi-Martan to expose members of the underground.