MOSCOW/BEIRUT (Reuters) - Russian long-range bombers struck Islamic State on Friday in Albu Kamal in eastern Syria, where the jihadists have staged a counter-attack after the Syrian army declared victory over them.

Six TU-22M3 bombers took off from bases in Russia and overflew Iran and Iraq before launching the strike, the Russian defense ministry said in a statement reported by Russian news agencies.

Albu Kamal, a small town on the border with Iraq, was Islamic State’s last Syrian stronghold, along with some neighboring villages and desert areas.

The Syrian army said it and its allies, including the Lebanese Hezbollah group, took it from the militants on Nov. 9 and declared “the fall of the terrorist Daesh organization’s project in the region”.

Islamic State fighters hidden in Albu Kamal launched a counter-attack days later and forced the army and its allies to pull out of Albu Kamal, residents said on Nov. 13.

The army, which has driven Islamic State from huge swathes of central and eastern Syria in a multi-pronged campaign this year, re-entered the town soon afterwards, a war monitor said.

TASS cited the ministry as saying the planes had bombed Islamic State fortified positions, militants, and armored vehicles. Satellite and drone surveillance had confirmed that all of the designated targets had been destroyed, it said.