Hours before a team of European Union officials landed in the war ravaged republic to check on the human rights situation, troops and polices swooped to down to wipe out what the military said were rebel groups.
"After the bandits refused to surrender, we started their elimination," Interfax news agency quoted a military spokesman in Chechnya as saying.
Russian official Akhmed Dikayev, told Interfax that troops had been sent to Argun after a four-vehicle Russian convey had been ambushed by guerillas. "There is a battle under way. There are casualties on both sides. Argun is fully blockaded," he said.
A rebel spokesman told Reuters that fighting had erupted in the town, just east of the capital city Grozny. "Fierce fighting is raging through the town, on every street, in every district," Movladi Udugov said by telephone.
The fighting followed several days of fighting across Chechnya, which prompted Russia to halt a troop withdrawal, and cast doubt on plans to return refuges from tent camps in neighboring Ingushetia.
The renewed violence is likely to spark new fears from the visiting Europeans about the fate of civilians in Chechnya, one of the main concerns of EU human rights monitors.
"What is happening in Chechnya concerns the whole of humanity because human rights are out common preoccupation," said Swedish Ambassador Sven Hirdman. He said that EU bodies had evidence of serious human rights violations in Chechnya and would bring up the issue with Russian leaders.
Last month the U.N. Commission on Human Rights voted to support an EU resolution condemning Russia for its "disproportionate" use of force in Chechnya and called for "credible criminal investigations" into alleged war crimes.
Russian troops were sent into Chechnya in 1999 to bring the territory back under its control. Despite almost daily attacks from the rebels, Russia claims that it has established a shaky control over the area and is making progress in restoring peace.
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