A number of Russians who went to fight in Ukraine are returning to Russia, where they oppose the government of Vladimir Putin.

Some of the activists, who organized protests against Putin in 2011 and 2012, are part of the Russian opposition’s right wing. Their political beliefs took them from the streets of Moscow to eastern Ukraine, where they defended the ethnic Russian population against the Ukrainian army, writes Courtney Weaver for The Financial Times.

Kremlin Worried By Russian Fighters Returning From Ukraine

Anti-Putin Russian nationalists returning from conflict in Ukraine

Although they agree with the Kremlin that the conflict in Ukraine is about defending ethnic Russians, the activists are still opposed to Putin’s government. One fighter, Oleg Melnikov, called Putin “ineffective and corrupt.”

Many of these fighters are now returning to Russia, and causing a headache for authorities. As Melnikov puts it, “all the people who travel to Donetsk to help the rebels they don’t necessarily support the Russian authorities — and now these people have military experience,” he said.

So far these volunteer fighters have received little coverage in the media, but there are scores of them, and many are returning home as the fighting in Ukraine dies down. Russia is not necessarily happy to have them back and has tightened security along the border with Ukraine.

Security stepped up to prevent development of anti-Putin force

Border guards are carefully checking vehicles for smuggled weapons, and Rossiyskaya Gazeta reports that 40 firearms, 6,000 rounds of ammunition and 200 grenades have been confiscated from smugglers.

Although the Border Guard Service denies that the border is subject to special measures, Alexander Verkhovsky, at Moscow’s Sova Centre think-tank, says that militants returning from Ukraine are being carefully watched. “We don’t know what the authorities are thinking. But I think law enforcement see [some of the returning fighters] as a problem. They are likely under close observation,” he said.

Another fighter, Andrei Ragulin, emphasized that he and Melnikov are in a minority of fighters who have such anti-Putin views. He says that they number in the hundreds, rather than thousands.

Melnikov plans to return to Russia, claiming that a “hard winter” was on its way for Russia, and former volunteer fighters could have an important role to play in developments.

“I think these people will let themselves be known at a certain moment when some big government decisions are being taken — through protests, resembling Maidan,” he said, in reference to the volunteer fighters. “As Maidan showed, a revolution comes not from 100,000 people standing around, but 1,000 radicals taking action.”

U.S. training Ukrainian troops, Russia sends bombers to Crimea

Not only are the pro-Russian rebels losing volunteer fighters back to Russia, they may soon face more Ukrainian troops that have received combat training from the U.S. Army. According to Reuters, the training is designed to shore up Ukrainian security given recent territorial losses to Russia.

Among those losses were the Crimean peninsula, which Moscow is apparently rearming with Tupolev Tu-22M3 long-range bombers, according to the BBC. The Kremlin apparently wishes to counteract the threat of proposed U.S. missile deployments in Romania and Poland, but many analysts have questioned whether the bombers will strengthen the Russian forces in the Crimea.

Others argue that stationing the bombers on the peninsula will allow Russia to project its power at times of international tension, and the Kremlin’s control of Crimea allows it to destroy any target in the Black Sea.