Russia’s drone attack on the Ukrainian port city of Odesa saw Moscow fire Iran-made drones at key infrastructure, Ukrainian officials said.

“The situation in the Odesa region is very difficult,” President Volodymyr Zelensky said in his nightly video address. “Unfortunately the hits were critical, so it takes more than just time to restore electricity. It doesn’t take hours, but a few days.”

Since October, Moscow has been targeting Ukraine’s energy infrastructure with large waves of missile and drone strikes.

In Melitopol, pro-Moscow authorities said a missile attack had killed two people and injured 10, while Ivan Fedorov, the exiled mayor, said scores of “invaders” had been killed.

“Air defence systems destroyed two missiles, four reached their targets,” Yevgeny Balitsky, the Moscow-appointed governor of the occupied part of the Zaporizhzhia region, said on the Telegram messaging app.

He added that a “recreation centre” where people were dining had been destroyed in the Ukrainian attack with Himars missiles.

Occupied by Russia since March, Melitopol has been described as key to the defence of the south by Oleksiy Arestovych, an advisor to President Zelensky.

“All logistics linking the Russian forces on the eastern part of the Kherson region and all the way to the Russian border near Mariupol is carried out through it,” Arestovych said in a video interview on social media.

“If Melitopol falls, the entire defence line all the way to Kherson collapses. Ukrainian forces gain a direct route to Crimea.”