KYIV ― Russia launched dozens of kamikaze drones and missiles at Ukraine’s cities and towns in the early hours of Monday, causing emergency electricity shut-offs in several cities.

The massive attack, which came in several waves and was continuing late morning, caused multiple explosions in Kyiv, Odesa, Kharkiv, Dnipro and many smaller cities of central and western Ukraine. Four people were reported killed in the strikes.

"Fifteen regions suffered today as a result of the massive Russian attack," Ukrainian Prime Minister Denys Shmyhal said in a post on Telegram. "Energy infrastructure has once again become the target of Russian terrorists," he added.

Monday's assault is Russia’s first large-scale attack with drones and missiles since Kyiv launched its surprise incursion into Russia's Kursk region earlier this month. Ukrainian forces took control of two more settlements in Kursk over the weekend, Ukrainian President Volodymyr Zelenskyy said in a statement Sunday evening.

The electricity shut-offs came just days after Ukraine’s state energy company Ukrenergo reported the system had returned to a stable energy flow.

"The transmission system operator has now entered the emergency power outage mode," Ukraine's Energy Minister Herman Halushchenko said in a statement Monday. "The situation is complicated; the results of the attacks are being clarified."

In the Dnipro region, one person was killed and several fires were reported, regional Governor Serhiy Lysak said in a Telegram post. In the capital of Kyiv, several districts were left without electricity and water, Mayor Vitaly Klitschko said.

Poland scrambled fighter jets due to the increased activity of Russian bombers barraging western Ukraine, though Warsaw still refuses to shoot down missiles over Ukraine. The last time Poland mobilized its military aircraft was during a massive attack on July 8, when Russia bombed the biggest children’s hospital in Kyiv.

In his Telegram post, Shmyhal renewed Kyiv's pleas for weapons and permission from Ukraine's allies to hit military targets in Russia. "In order to stop the barbaric shelling of Ukrainian cities, it is necessary to destroy the place from which the Russian missiles are launched," he said. "For this, Ukraine needs long-range weapons and the permission of its partners to hit Russian objects with them."