In this file photo, a Tajik frontier guard patrols the border at the Tajik-Afghan border not far from the town of Pyandj, some 220 km from Dushanbe. (VYACHESLAV OSELEDKO / AFP)

MOSCOW - Russian military helicopters based in Tajikistan fired air-to-surface missiles during a training exercise on Tuesday as Moscow said its forces in the Central Asian nation were fully equipped to help secure the border with Afghanistan.

Tajik President Emomali Rakhmon on Monday ordered the mobilization of 20,000 military reservists to bolster the border with Afghanistan after more than 1,000 Afghan security personnel fled across the frontier in response to Taliban militant advances.

Tajik President Emomali Rakhmon ordered on Monday the mobilization of 20,000 military reservists after more than 1,000 Afghan security personnel fled across the frontier in response to Taliban militant advances

Russian President Vladimir Putin told Rakhmon on Monday that Moscow would help the impoverished former Soviet republic contend with the fallout from NATO's exit from neighboring Afghanistan if necessary.

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Russia, which operates one of its largest military bases abroad in Tajikistan equipped with tanks, helicopters, drones and ground attack aircraft, would help stabilize the border with Afghanistan if needed, both directly and through a regional security bloc, the Kremlin said in a statement.

Russia's Deputy Foreign Minister Andrei Rudenko repeated that pledge on Monday and was cited by the Interfax news agency as saying it appeared that the Taliban was now in control of most of the border on the Afghan side.

"The situation there is rather tense because according to some sources, up to 70% of the Tajik-Afghan border is now controlled by the Taliban," Rudenko was quoted as saying.

Russia's defense ministry said on Monday that two MI-24 attack helicopters and two military transport helicopters had taken part in a training exercise in Tajikistan during which unguided missiles had been launched at more than 15 ground targets.

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The exercise had simulated an attack on illegal armed groups along with a convoy of cars, enemy firepoints and arms caches.