Editor's note: The story was updated with comments from Ukraine's military intelligence agency.
Following over a week of cross-border raids, the Ukrainian-equipped anti-Kremlin militias held a joint press conference in downtown Kyiv to have their voices heard.
With the recent incursions, the Ukraine-led militants say their goal was to "open a second front" and ease pressure on Ukrainian troops on the Kupiansk axis.
Russian nationalist Denis Kapustin, commander of the right-wing Russian Volunteer Corps, said that the fighters of the units "stabilized the front" and "eased the pressure of Russian troops in certain areas."
Kapustin, a controversial figure banned from entering the EU, was joined by Alexei Baranovsky, the Freedom of Russia Legion volunteer and a soldier of the brand-new Siberian Battalion known only by his call sign "Kholod."
Their units' raids, which they call "a limited military operation," are still reportedly underway in Belgorod and Kursk oblasts.
Baranovsky claimed that anti-Kremlin forces had received intelligence about Russia's alleged plans to advance further into Kharkiv Oblast.
"Our operation in the military sense disrupted the plans of the Russian army and caused significant damage to it. They were forced to move significant forces from the Kupiansk sector in order to hold their Belgorod Oblast," Baranovsky alleged.
The Kyiv Independent couldn't verify these claims.
Russian troops intensified their attacks in the Kupiansk sector in January and captured the village of Krokhmalne, Kharkiv Oblast. As of mid-February, Ukrainian intelligence said that Moscow did not have enough resources for a new large-scale offensive in the region.
Andriy Yusov, spokesperson of Ukraine's military intelligence agency (HUR), said that Ukraine "helped volunteer groups," who, according to him, "act absolutely autonomously" once in Russia.
When asked by the Kyiv Independent about the scale of such help to anti-Kremlin militias, Kapustin answered that the Russian Volunteer Corps could rely on logistics, intelligence, and evacuation of wounded soldiers from the Ukrainian side.
All the "military infrastructure" of the unit is interconnected with the infrastructure of the Armed Forces of Ukraine, he said.
"Therefore, we receive the necessary amount of support from the Ukrainian side in order to carry out our combat missions on Russia's territory," Kapustin told the Kyiv Independent.
Yusov confirmed to the Kyiv Independent that militias' raids on Russian territory made Moscow "change plans for the northern sector of Ukraine." Recently, Kyiv has recorded an increase in the threat in this area, including from Russian sabotage and reconnaissance groups, according to HUR’s spokesperson.
After last year's raids, the media reported that Russian volunteers allegedly used tactical vehicles provided to Ukraine by the U.S. and Poland and had rifles made in Belgium and the Czech Republic. Belgian Prime Minister Alexander de Croo said back then that Brussels was investigating the reports.
This time, the Russian Defense Ministry published footage depicting several disabled pieces of hardware, including a tank and a U.S.-made Bradley Fighting Vehicle.
The videos couldn't be independently verified.
“Western samples are the weapons that the enemy captured once, and they were later taken back from the Russian forces,” Yusov told the Kyiv Independent, when asked about the weapons used by the units.
The spokesmen denied saying whether they used Western-provided weapons.
"When we are on Ukraine's territory, we are servicemen of the Ukrainian army, equal in all rights and duties to Ukrainian servicemen. When we enter Russia's territory, we are not Ukraine's soldiers, we are citizens of Russia who have taken up arms," Baranovsky said.
According to him, the militias have weapons in their arsenal issued to them as a structural unit of the International Legion of the Armed Forces of Ukraine.
They also have trophy weapons, recaptured weapons — which Russian troops once captured from Ukrainian fighters and anti-Kremlin forces took them back — and "various Ukrainian-made equipment," Baranovsky told journalists.
According to the anti-Kremlin fighters, the scale of the breakthrough into Russian territory, along with the amount of equipment and the number of personnel used, was much larger than previous such attacks in the spring and summer of 2023.
According to the fighters, Russia has lost over 1,500 soldiers killed and wounded and more than 100 pieces of equipment. The number is questioned by experts and believed to be significantly exaggerated.
Another 37 Russian servicemen were reportedly captured. Some of them, according to Kapustin, wanted to join the Russian Volunteer Corps.
This may happen after background checks, otherwise, the prisoners of war will be handed over to Ukraine.
They added that the units taking part in the operation will disclose their own losses when the operation is over.
"The primary task is to help Ukraine's Armed Forces win this war and defend the territorial integrity of Ukraine," Kapustin said.
"Our ultimate goal is to keep on our liberation campaign, to deconstruct the regime that has been strangling our homeland for decades. Even after Ukraine's victory for the Russian Volunteer Corps, this war will continue," he added.