Ukrainian President Volodymyr Zelenskiy said on December 14 that Moscow has started involving more North Korean troops in its efforts to drive Ukrainian forces out of Russia's Kursk region.
"Today there are already preliminary data that the Russians have begun using soldiers from North Korea in the assaults -- a noticeable number," Zelenskiy said.
"The Russians include them in consolidated units and use them in operations in the Kursk region. For now, it is only there."
Zelenskiy’s comments came after the Main Intelligence Directorate of the Ukrainian military (HUR) issued a statement saying that North Korean troops probably will begin assaulting Ukrainian military positions in the Kursk region in the near future.
The HUR said it was "likely" that Russia will soon involve North Korean soldiers in direct assault operations, noting that in recent days the troops "received additional food supplies."
The North Korean units on December 13 were put on alert and ordered to wait for further instructions, the HUR said.
Some of the troops have been covertly transferred to the front line by civilian trucks that outwardly resemble water-delivery vehicles, the statement said.
It was not possible to verify the information, and the Russian Defense Ministry has not commented on it.
Ukrainian troops began their incursion into the Kursk region in August and still control some areas. Russia began deploying thousands of North Korean troops in the region in October.
The General Staff of the Ukrainian military said on December 14 that 45 clashes had taken place since the beginning of the day in the Kursk region, and 26 of them were still ongoing.
"In addition, the enemy carried out seven air strikes, dropping 10 guided bombs and carrying out 212 artillery attacks on Russian settlements and the positions of our defenders," the General Staff said in its daily summary.
The summary added that the most tense situations on the battlefield were taking place in areas near Pokrovsk, Kurakhivsk, and Vremivsk.
The Russian military "improved the tactical position" in the Pokrovsk direction, the press service of the Khortytsia Military District reported.
Russian forces also tried to improve their tactical position in the Blahodatne area, but were not successful, suffered losses, and withdrew.
Ukrainian forces mounted their own attacks on facilities that supply petroleum products to the Russian Army, the General Staff said.
An attack on a Russian oil depot in Orel overnight on December 13 started a "powerful fire," according to a statement from the General Staff, which described the depot as one of the largest oil terminals in the suburbs of Orel.
Reports of explosions in Orel appeared earlier on Russian Telegram channels. The city was reportedly hit by drone strikes, and some of the channels reported an attack on a local oil depot.
Photos published by the General Staff and on Russian Telegram news channels showed plumes of smoke engulfing the oil terminal.
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Local authorities and Russian state media did not comment on the reports.
Russia's Orel region borders the Kursk and Bryansk regions.
In the border region of Belgorod, Ukrainian drone strikes killed a 9-year-old boy and set fire to a major oil terminal there, Governor Vyacheslav Gladkov said on Telegram.
The boy died when a drone struck his family's home outside Belgorod, Gladkov said, adding that his mother and 7-month-old sister were hospitalized.
He posted photos of what he said was the aftermath of the attack, showing a house with gaping holes in its roof and front wall flanked by mounds of rubble.
Orel Governor Andrei Klychkov confirmed on Telegram that a Ukrainian drone strike set fire to a fuel depot. He said later that the blaze had been contained and that there were no casualties.