Second Chechen War ( ) , also known as the Second Chechen Сampaign ( ) or officially ( from the Russian point of view ) Counter-terrorist operations on territories of North Caucasian region ( ) , was an armed conflict on the territory of Chechnya and the border regions of the North Caucasus between the Russian Federation and the Chechen Republic of Ichkeria , also with militants of various Islamist groups , fought from August 1999 to April 2009 .