Earlier this year, a contingent of U.S. Special Operations troops working alongside Syrian Democratic Forces (SDF) in Syria were engaged in a four-hour long firefight against a Syrian government-backed force of some 500 troops. Among those pro-Assad troops, it was reported at the time, were a number of Russian civilians — widely recognized among those in the region as mercenaries working indirectly for the Kremlin, but formally unacknowledged by the Russian government.

The firefight may have opened with a barrage of artillery from Pro-Assad forces, but the tides quickly turned as American air support arrived to beat back the advance. When the dust settled, not one of the forty Americans that took part in the firefight were injured, but media estimates place the number of Russian and Pro-Assad dead at somewhere in the neighborhood of 300. The remnants of the attacking contingent were allowed to retreat without incident.

In the following days, the world waited with bated breath to see how the Kremlin would respond to hundred of Russians dying in a firefight against American troops… but as the days wore on, Russia offered no harsh statements or threats of war. Instead, they began to distance themselves from the Russian men that had died in the fight. Russia’s official line on the incident was that any Russians involved in the offensive were volunteers who had gone to Syria of their own accord to support a cause they felt was just.

Similar incidents of Russian “civilians” engaging in clearly military activities have permeated throughout conflict zones with Russian involvement. Pro-Russian separatists in Ukraine, for instance, found a great deal of support in their civil war against the nation’s formal government in the form of plain-clothes wearing Russian soldiers. These soldiers, according to Moscow, were also volunteers.

Russia’s government may be willing to look the other way as their troops are killed in combat without any official recognition or support — but Russia’s veteran population is now taking it upon themselves to address what they are calling war crimes.

According to reports from within Russia, more than a dozen veteran organizations have written to Hague-based war crimes prosecutor Fatou Bensouda, calling on him to lead an investigation into Russia’s efforts to enlist mercenaries for combat operations abroad that then go unrecognized by the Russian government.

Russian T-72 Battle Tank destroyed by airstrike after engaging US Special Operations troops in Syria

Read Next: Russian T-72 Battle Tank destroyed by airstrike after engaging US Special Operations troops in Syria

“The Russians fight abroad as ‘volunteers’ and without any official recognition from the Russian government,” said Yevgeny Shabayev, a paramilitary Cossack group leader. “In fact, Russian civilians … are being sent out of their country of residence to be illegally used for military purposes.”

Although more than a dozen veteran organizations have joined this call, it remains unclear just how many of the estimated hundreds of thousands of veterans within Russia are actually represented by these groups. Nonetheless, public outcry against Putin’s use of civilian mercenaries for the sake of plausible deniability is a black eye for the Kremlin, who repeatedly claims to have no affiliation with the Russian “civilians” fighting on foreign soil. The outcry alone creates a crack in the facade of Russia’s disinformation efforts regarding their ongoing campaigns in places like Ukraine.

Whether or not the investigation will actually manifest, however, remains to be seen. According to Shabayev, who claims to know dozens of Russian soldiers that have been called on to serve as mercenaries for the Russian government, many Russians would be willing to testify in international courts — provided they were given protection from Russian government reprisal. Moscow has been implicated in the assassinations and attempted assassinations of many of Russian president Vladimir Putin’s opponents.

“It will depend on whether the West is really interested to examine the situation,” Shabayev said.