Moscow's FSB security service said on Friday it had arrested two Russian citizens for passing information about the country's military to Ukraine.
Russia has arrested several of its own citizens it says have worked with Ukraine or funded the Ukrainian army since Moscow launched its full-scale military offensive in February 2022.
The FSB said on Friday it had arrested two men in the southern city of Rostov-on-Don on treason charges -- crimes that carry up to 20 years in prison.
"According to an investigation, they proactively established contact with a representative of the Ukrainian security services.
In the course of their communications, they agreed to collect and transmit information about units of the Russian armed forces taking part in the special military operation," the FSB said, using Moscow's prefered language for its military campaign.
It alleged the pair were paid for providing information on the location of military equipment and personnel.
Rostov-on-Don is the command headquarters for Russia's offensive on Ukraine.
The city is located on the Sea of Azov and is fewer than 100 kilometres (60 miles) from the border with Ukraine's Donetsk and Lugansk regions -- two of the four regions that Moscow claims to have annexed.
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