GROZNY, April 22 (RIA Novosti) - Three servicemen died in Russia's North Caucasus republic of Chechnya after their vehicle came under fire, a police source said on Wednesday.

The attack occurred on Tuesday in southern Chechnya's Achkhoi-Martan region. A police official said a search was underway for the assailants.

The counter-terrorism operation in Chechnya was officially concluded on April 16, almost ten years after its inception. The Russian government's decision to end the operation will entail the withdrawal of tens of thousands of troops from the region.

Russian military officials said earlier this week that militant activity in Chechnya had sharply increased since the announcement, and that militants were organizing a network of bases. Chechen President Ramzan Kadyrov has dismissed the report.