The Ukrainian president has urged citizens to be vigilant ahead of celebrations on Wednesday, August 24 that will mark 31 years of independence from Soviet rule. Zelensky said Ukrainians should not allow Moscow to “spread despair and fear” ahead of the national holiday, which is to be held exactly six months after Vladimir Putin launched his invasion of Ukraine. But he warned on Saturday in his nightly address to Ukrainians: “We should be aware that this week Russia may try to do something particularly bad, something particularly cruel. Such is our enemy. “But in any other week during those six months, Russia did the same thing all the time – disgusting and cruel.” “One of the main tasks of the enemy is to humiliate us, the Ukrainians, to underestimate our capabilities, our heroes, to spread despair, fear, to spread conflicts… Therefore, it is important never, not even for a moment, to we give to this the pressure of the enemy, not to wind up, not to show weakness”. Residents of Kharkiv, Ukraine’s second-largest city regularly hit by Russian missiles, will be under a curfew for the rest of Wednesday, regional governor Oleh Synehub said. Volodymyr Zelensky gives his nightly speech to Ukrainians (Office of the President of Ukraine) “Stay at home and heed the warnings!” he wrote to residents on the Telegram messaging app. In his speech, Mr Zelensky also indirectly referred to a series of explosions earlier on Saturday in Crimea, the Ukrainian territory annexed by Russia in 2014. He said: “You can literally feel Crimea in the air this year, that the occupation there is only temporary and that Ukraine is coming back.” Mikhail Razvozayev, the Moscow-appointed governor of Sevastopol, Crimea’s largest city, said a Ukrainian drone struck a building near the headquarters of Russia’s Black Sea Fleet on Saturday morning. “A drone flew over the roof. He was flying low,” he told Telegram. “It crashed right over fleet headquarters. He fell on the roof and burned. The attack failed.” It was the second drone incident at headquarters in three weeks. This month also saw several explosions at a Russian airport and ammunition depot on the peninsula. The headquarters of the Russian Black Sea Fleet in Sevastopol (AFP via Getty Images) Moscow’s forces there are on “high alert” and have found themselves “much more vulnerable than they thought they were,” a senior US defense official said – as reported by the Washington Post. This weekend, fighting has intensified in eastern Ukraine’s Donbas region, while “strong explosions” rocked Melitopol in the south of the country, according to local mayor Ivan Ferodov. Also in southern Ukraine, a rocket injured 14 civilians – including four children – in Voznesensk, a town 20 miles (30 kilometers) from the Pivdennoukrainsk nuclear power plant, also known as the Southern Ukraine Nuclear Plant. Vitaliy Kim, governor of the Mykolaiv region, told Telegram that children were among the injured – with one losing an eye – when houses, including a five-storey apartment building, were hit. Damaged Russian military vehicles are on display in Kyiv ahead of Independence Day (Andrew Kravchenko/AP) The Voznesensk attack was “another act of Russian nuclear terrorism,” said state-run Energoatom, which runs Ukraine’s four nuclear power producers. “It is possible that this missile specifically targeted the Pivdenukrainsk plant, which the Russian military tried to retake in early March,” it said in a statement. Russia did not immediately respond to the accusation. Reuters news agency said it could not verify the situation in Voznesensk and that there were no reports of damage at the southern Ukrainian plant. Earlier this week, missiles hit the Russian-held Zaporizhzhia nuclear power plant in an attack that Ukraine and Russia have blamed on each other. Vladimir Rogov, a Russian-appointed official in the nearby town of Enerhodar, said Ukrainian forces had launched at least four raids on the plant. Across the Dnipro River, directly across from the Zaporizhzhia nuclear power plant, the city of Nikopol was repeatedly shelled by Russian forces on Wednesday night, according to local mayor Yevhen Yetushenko. Ukrainian officials said the missile attacks on the two power plants – the two largest in Europe and Zaporizhia, Europe’s largest – had reignited fears of a nuclear catastrophe.