A court in Moscow convicted two Russians of setting up an illegal mercenary squad, the first sentence in the country's history to be handed down on those charges, Life News reported Tuesday.
Vadim Gusev and Pavel Sidorov were found guilty of deploying a 250-person unit in 2013 to fight in Syria's civil conflict, the news website said.
Each faced up to eight years behind bars, but got away with three-year sentences at a closed trial. It was not immediately clear whether Gusev or Sidorov planned to appeal.
The story was first reported by Islamist militants waging war on Syrian President Bashar Assad. The militants said they had routed some Russian mercenaries and published copies of IDs they said they seized in the process.
Life News said the Russians had been fighting against Assad, which contradicts previous reports, including video testimony by former squad members.
Rank-and-file squad members later said they were promised a relatively safe — and Kremlin-endorsed — job of protecting Syrian power plants.
But the ragtag band of Russian army and police veterans and Cossacks, dubbed the "Slavonic Corps," was instead sent on a 500-kilometer raid into enemy territory.
Slavonic Corps members interviewed by the Fontanka.ru news website last year said the squad had 267 members and lost no troops to the enemy, despite the decrepit equipment they were given to operate.
Syrian Islamists claimed to have killed at least several squad members. The discrepancy could not immediately be reconciled.
Regular squad members faced no prosecution in Russia, but neither were they reported to have been paid.
The Russian parliament is currently mulling the legalization of private military companies, a move endorsed in 2012 by President Vladimir Putin, but not legislated so far.
Media reports have claimed that Russian mercenaries fought for the separatists in the Ukrainian civil war earlier this year, but official Moscow denied it.