Russia also struck military bases in central and eastern Ukraine, according to the Ministry of Defense, cited by Russian media.
In response to recent attacks on Russian power plants from Moscow to the Black Sea, they claimed to have struck Ukraine’s defense and energy infrastructure.
The attacks led to a rare concession by Russian President Vladimir Putin that his country was facing fuel shortages.
On Wednesday, Zelensky cut short his visit to Dublin after saying new intelligence had emerged suggesting Moscow was planning to strike Ukraine.
“I urge our people to be especially careful, to protect themselves, their children and, of course, their families,” he said.
He added that Russian President Vladimir Putin “has been preparing this massive attack on Ukraine for some time.”
Russian troops recently entered the city of Konstantinovka, one of Ukraine’s last key swamps in the east. If Moscow defends the city, it will become a gateway to the entire Donbass.
Meanwhile, Ukrainian commanders say they have regained more territory this year than they lost, disrupting Moscow’s vital supply lines between the Russian border and occupied Crimea.
The land war otherwise stalled for several months, with each side’s troops largely entrenched in their positions.
Russia controls about one-fifth of Ukraine’s territory, mostly captured in the first few months of its full-scale invasion in February 2022.