Russia launched more than 100 missiles and around 100 attack drones at Ukraine during the morning rush hour on Monday, killing at least five people and striking energy facilities nationwide, officials said.

Power cuts and water supply outages were reported in numerous places, including parts of Kyiv, as officials said the attack targeted power or other critical infrastructure in at least 10 regions.

Russia dramatically stepped up its strikes on the Ukrainian power grid in March in what Kyiv has said looks like a concerted effort to degrade the system ahead of winter when people need electricity and heating most.

Monday’s missile and drone salvo was Russia’s most intense in weeks, coming as Ukraine is claiming new ground in a major cross-border incursion into Russia’s southern Kursk region while Russian forces steadily inch forward in Ukraine’s east, closing in on the transport hub of Pokrovsk.

“It was one of the biggest combined strikes. More than a hundred missiles of various types and about a hundred Shahed drones. And like most previous Russian strikes, this one is just as sneaky, targeting critical civilian infrastructure,” President Volodymyr Zelensky of Ukraine said on Telegram.

According to Prime Minister Denys Shmyhal, 15 regions had sustained damage. Zelensky said the energy sector had taken “a lot of damage”.

Ukraine had no powerful long-range weapons at the start of the invasion, but has since developed many models of long-range attack drones and used them to hit targets deep inside Russia, ranging from oil refineries to military airfields.

Over the weekend, Zelensky said Ukraine had developed a new “drone missile” that had been used to attack Russia and was more powerful and faster than other hardware in Kyiv’s arsenal.

Interfax news agency cited Russia’s defence ministry as saying on Monday its forces used high-precision weapons to strike important energy infrastructure in Ukraine which it said supported the military-industrial complex.

Poland’s military said its warplanes and those of its allies had been put on alert after the Russian missile and drone assault, which struck western regions of Ukraine that border the Nato member state.

The regions with targeted power or critical infrastructure included Rivne and Volyn in the northwest, Khmelnytsk in the southwest, Zhytomyr in the north, Lviv in the west, Dnipropetrovsk, Kirovohrad and Vinnytsia in central Ukraine, Zaporizhzhia in the southeast and Odesa in the south.

At least seven of those regions had facilities that were hit or damaged, officials said.

Neighbouring Moldova, whose grid is linked to that of Ukraine, reported small disruptions to its power network.

In the northeastern Sumy region, from where Ukraine launched its incursion into Russia on August 6, authorities said a railway infrastructure facility had been struck, but did not say which one or give further details.

A 69-year-old man in Dnipropetrovsk was among at least five people confirmed dead, local officials said. The others were in the regions of Zaporizhzhia, Kharkiv, Zhytomyr and Volyn.

In Lutsk, an apartment block was damaged, the mayor said after reporting explosions. Blasts also shook central Kyiv and air defences could be heard engaging incoming targets on the outskirts of the capital.

The air force said Russia used 11 TU-95 strategic bombers during Monday’s attack, as well as other weaponry.

Ukrainians had been expecting a major Russian missile attack for some time. The US embassy issued a warning last week of an elevated risk of attack around Ukrainian Independence Day, which Ukraine marked on Saturday.

Around 15 missiles and 15 drones targeting Kyiv were downed, Serhiy Popko, head of Kyiv’s military administration, wrote on Telegram.

Russia said on Monday it had struck Ukrainian forces at more than a dozen places along the front in the Kursk region of western Russia where Ukraine has carved out a slice of territory after smashing through the Russian border 20 days ago.