Ukrainian president Volodymyr Zelenskyy denies the besieged city of Bakhmut has fallen to Russia after months of bitter fighting. Russian forces claimed victory this weekend, but Ukrainian forces say they’re still active in the city and even gaining ground.

KYIV, Ukraine β€” Russian officials claimed that Ukrainian military saboteurs launched an attack across the border Monday, wounding eight people in a small town. Kyiv officials denied any link with the group and blamed the fighting on a revolt by disgruntled Russians against the Kremlin.

A Russian serviceman guards an area of the Zaporizhzhia Nuclear Power Station on May 1, 2022, in territory under Russian military control, southeastern Ukraine.

Neither version of events could be independently verified in an area that has witnessed sporadic spillover from the almost 15-month war in Ukraine.

The governor of Russia’s Belgorod region, which borders Ukraine, said that a Ukrainian Armed Forces saboteur group entered the town of Graivoron, about 3 miles from the border. The town also came under Ukrainian artillery fire, he said.

Gov. Vyacheslav Gladkov said eight people were wounded and most residents had left the area, but the situation remained β€œtense.”

In nearby Zamostye village, a projectile hit a kindergarten and caused a fire. One woman was wounded in her hand, Gladkov said. He also reported that Russian anti-aircraft systems shot down an unmanned aerial vehicle over Belgorod region.

Gladkov said a counterterrorist operation was underway and that authorities were imposing special controls, including personal document checks and stopping the work of companies that use β€œexplosives, radioactive, chemically and biologically hazardous substances.”

Kremlin spokesman Dmitry Peskov said Russian President Vladimir Putin was informed about the alleged saboteur incursion. An effort to β€œpush them out from the Russian territory and liquidate them” was underway, he said.

But Ukrainian military intelligence officials didn’t confirm that Kyiv had deployed saboteurs. Instead, they claimed that Russian citizens seeking regime change in Moscow were behind the Graivoron incursion.

Ukraine intelligence representative Andrii Cherniak said Russian citizens belonging to murky groups calling themselves the Russian Volunteer Corps and the β€œFreedom of Russia” Legion were behind the assault.

Ukrainian President Volodymyr Zelenskyy’s adviser, Mykhailo Podolyak, said on Twitter that Ukraine β€œhas nothing to do with it.” He suggested an β€œarmed guerrilla movement” was behind the attack.

A Ukrainian soldier smiles atop an APC on the frontline Sunday in the Luhansk region, Ukraine.

The Russian Volunteer Corps claimed in a Telegram post it had crossed the border into Russia again, after claiming to have breached the border in early March.

The Russian Volunteer Corps describes itself as β€œa volunteer formation fighting on Ukraine’s side.” Little is known about the group, and it is not clear if it has any ties with the Ukrainian military. The same is true for the β€œFreedom of Russia” Legion..

The RVC was founded last August and reportedly consists mostly of anti-Putin far-right Russian extremists who have links with Ukrainian far-right groups.

Earlier Monday, Ukraine’s Zaporizhzhia Nuclear Power Plant, Europe’s largest atomic power station, spent hours operating on emergency diesel generators after losing its external power supply for the seventh time since Russia’s full-scale invasion of its neighbor, the head of the U.N. nuclear watchdog said.

β€œThe nuclear safety situation at the plant (is) extremely vulnerable,” Rafael Grossi, head of the International Atomic Energy Agency, said in a tweet.

Hours later, national energy company Ukrenergo said on Telegram that it had restored the power line that feeds the plant.

But for Grossi, it was another reminder of what’s at stake at the Russian-occupied plant which has seen shelling close by.

β€œWe must agree to protect (the) plant now; this situation cannot continue,” Grossi said, in his latest appeal for the area to be spared from the fighting between Ukrainian and Russian forces. IAEA staff are deployed at the plant, which is occupied by Russian troops.

The plant’s six nuclear reactors, which are protected by a reinforced shelter able to withstand an errant shell or rocket, have been shut down. But a disruption in the electrical supply could disable cooling systems that are essential for the reactors’ safety even when they are shut down. Emergency diesel generators, which officials say can keep the plant operational for 10 days, can be unreliable.

Meanwhile, Russian TV went into a full frenzy of celebration as it reported Moscow’s capture of the Ukrainian city of Bakhmut. There were comparisons to the Red Army liberating Berlin in 1945, congratulations relayed from President Vladimir Putin and announcers emphasizing the victory by using the city’s nearly century-old Soviet name of Artyomovsk.

β€œThe myth that Artyomovsk is an unassailable fortress has been crushed,” an anchor said Sunday night on Channel One, Russia’s most popular state broadcaster. β€œThose are historic events.”

A report from the smoldering city in eastern Ukraine followed, showing Russian fighters yelling β€œVictory!” and placing two flags β€” the Russian tricolor and the black flag of the private military contractor Wagner β€” atop a tall, partly destroyed building.

The flags were mounted β€œso that everyone could see them,” the correspondent said, even though the bombed-out, deserted 400-year-old city looks like a ghost of itself after the longest and bloodiest battle of the war.

Despite the Russian claims, top Ukrainian military leaders say the fight there is not over, even though they still control only a small part of the city.

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