Ukrainian President Volodymyr Zelenskiy has hailed the new long-range capabilities of his military’s combat drones following reports of attacks deep inside Russian territory.
"In these weeks, many have already seen that the Russian system of warfare has weak points and that we can reach these points with our weapons," Zelenskiy said in his nightly video address on March 16.
He did not name a specific attack but the remarks came after reports that three oil facilities in Russia's Samara region -- more than 1,000 kilometers inside Russia -- had been set ablaze in drone attacks on March 15.
Earlier on March 16, Ukrainian forces launched multiple attacks on Russia, killing at least three people in the border city of Belgorod and hitting an oil refinery in the Samara region, Russian officials said.
A man and two women died in the Ukrainian shelling that also wounded three others in Belgorod, regional Governor Vyacheslav Gladkov wrote on Telegram.
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The official added that five people were also wounded when a Ukrainian drone hit a car in the village of Glotovo, some 2 kilometers from the Ukrainian border.
A Ukrainian drone strike caused a fire at an oil refinery that belongs to Russian oil giant Rosneft in the Samara region, some 850 kilometers southeast of Moscow, regional Governor Dmitry Azarov said. There were no immediate reports of casualties.
Social-media videos showed images of buildings on fire. Azarov said that an attack on another refinery was thwarted.
The attacks come a day after a Russian ballistic missile strike killed at least 20 people and wounded more than 70 others in the southern Ukrainian city of Odesa.
Two Iskander-M missiles fired from Russian-occupied Crimea struck a residential area in Odesa on March 15, Governor Oleh Kiper said.
Several of the victims were medics and rescuers who were killed by a second missile after they rushed to the scene to treat people hurt in the initial strike, Kiper added.
In his evening video address on March 15, Zelenskiy vowed that Russia would receive a "fair response" from Kyiv's forces.
On March 16, Russia's Federal Security Service (FSB) said it had detained a 61-year-old Russian man for planning what it called a terrorist attack on Ukraine's behalf on a trans-Siberian railway junction in the Ural Mountains' Sverdlovsk region.
State news agency TASS quoted the FSB as saying the man had been recruited by Kyiv's intelligence services in the western Ukrainian city of Lviv and sent to Russia. The agency said the man had confessed to the charges and was cooperating with the investigation.
Ukraine has previously said it was targeting the trans-Siberian railway, a key route for Russian freight traversing the country.
The March 16 Ukrainian attacks come as Russia entered the second day of voting in a presidential election that is all but certain to extend Vladimir Putin’s rule by another six years after he crushed dissent. Putin has accused Kyiv of trying to disrupt the election.