At least three people were killed in Ukrainian attacks on the Russian border town of Belgorod on March 16, while an oil refinery was hit in the Samara region.
Regional governor Vyacheslav Gladkov said that a man and two women were killed and three more people were wounded in Belgorod. He also said that five more people were wounded when a Ukrainian drone hit a car in the village of Glotovo, two kilometers from the border.
A Ukrainian drone strike caused a fire at an oil refinery belonging to Russian oil giant Rosneft in the Samara region, some 850 km southeast of Moscow, regional governor Dmitri Azarov said.
He also said that the attack on the second refinery was prevented. There is no information on possible victims.
The attacks come a day after a Russian attack on Odessa killed at least 20 people and wounded 70. Ukrainian President Volodymyr Zelensky said that the Russian forces that attacked Odesa on March 15 will receive a "fair response" from the Kiev forces.
Russia's Federal Security Service (FSB) said it had arrested a 61-year-old Russian man for planning what it called a terrorist attack on behalf of Ukraine in the Sverdlovsk region.
The state news agency TASS reported a statement by the FSB that the man was recruited by the Kiev intelligence service in Lviv and sent to Russia. They stated that the person confessed to everything and is cooperating with the investigation.
Ukraine has previously said it is targeting the Trans-Siberian Railway, a key route for Russian cargo passing through the country.
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