Kyiv, Ukraine CNN  — 

A fresh barrage of Russian missile attacks across Ukraine on Friday morning put the entire country under air-raid alarm and sent people scrambling for shelter as explosions sounded overhead, with strikes hitting critical infrastructure and knocking out power.

“They have set a goal to leave Ukrainians without light, water and heat,” Ukraine’s Prime Minister Denys Shmyhal told a government meeting, adding that 60 of the 76 missiles fired at Ukraine were intercepted by its air defense forces.

Russia’s persistent and pervasive attacks on Ukraine’s energy grid have, at least temporarily, left millions of civilians without electricity, heat, water and other critical services in the freezing winter months. Repeated missile and drone attacks since October, which have damaged or destroyed civilian infrastructure, are part of a strategy by the Kremlin to terrorize Ukrainians and is in violation of the laws of war, according to experts.

Ukrainian energy operator Ukrenergo reported on Friday that more than 50% of the country’s energy capacity was lost due to Russian strikes on thermal and hydroelectric power plants and substations, activating “emergency mode.”

Civilians shelter inside a metro station during an air raid alert in the centre of Kyiv.

“The enemy is massively attacking Ukraine. Increased danger. Stay in shelters,” Oleksiy Kuleba, the head of the Kyiv regional military administration, wrote on the Telegram messaging app, asking residents not to ignore the alarm.

Kyiv’s mayor, Vitali Klitschko, said explosions had hit the city and that three districts had been struck in the onslaught of rockets, disrupting water supplies across the capital. He suggested residents prepare a stock of drinking water while technicians work to restore the supply, and not to leave shelters as attacks continued.

Residents bundled in winter coats, hats and scarves gathered in Kyiv’s underground stations as the sirens wailed. Huddled on escalators, their faces were lit by their phones as they scrolled through updates.

One photo shared by authorities in the Kyiv region showed the fragments of a missile in the snow, which it said the air defense system had downed. Kyiv city’s military administration claimed that 37 of 40 missiles targeted at the capital were intercepted.

Regional and city authorities across the country reported explosions and missile strikes hitting civilian infrastructure, and leading to some deaths.

In the central city of Kryvyi Rih, officials said a Russian missile had hit a three-story residential building, killing at least two people and that emergency services were digging through the wreckage. “There may be people under the rubble,” the deputy head of the presidential administration, Kyrylo Tymoshenko, said.

A residential building damaged by a Russian missile in Kryvyi Rih.

At least 10 missiles struck various targets in Kharkiv region, in the north, damaging energy facilities and a hospital, according to Oleh Syniehubov, head of the regional military administration. Power was beginning to be restored in Kharkiv city after being knocked out for much of the day. “There is a colossal infrastructural damage,” Kharkiv’s mayor, Ihor Terekhov, said, instructing residents to use so-called “invincibility points” – makeshift centers offering relief from power outages – to collect food and hot drinks, and recharge cellphones.

The southeastern region of Zaporizhzhia was hit by more than a dozen missile strikes, according to Oleksandr Starukh, chief of the regional military administration, but it was unclear what had been targeted.

Meanwhile, artillery and rocket attacks continued in the southern city of Kherson, which was liberated by Ukrainian forces in November, targeting critical infrastructure, residential buildings, medical aid and public transport, leaving four dead, according to the head of the region’s military administration. Shelling also set a multi-storey apartment building ablaze, and the body of a man was found in one apartment, the Ukrainian Prosecutor-General’s Office said. The city is still struggling to restore basic services.

Sections of the Ukrainian railway system in Kharkiv, Kirovohrad, Donetsk and Dnipropetrovsk region were out of power following the strikes, and back-up diesel locomotives were replacing some services. Ukraine’s energy minister, Herman Halushchenko, said that nine power-generating facitilites were damaged in Friday’s attacks, and warned of more emergency blackouts.

Oleksandr Kharchenko, director of the Energy Industry Research Center, a Ukrainian research and consulting company, said on Ukrainian TV that power outages had been rolled out prior to the strikes as a preventative measure to protect the grid from blackouts. He added that, in spite of this, the result of the attacks Friday morning would be “unpleasant.”

“Unfortunately, we already see that they (Russians) are striking at the generating facilities again, trying to cut off our nuclear and thermal power plants, to damage additional key energy hubs, focusing their attacks on these facilities,” Kharchenko said. “I urge Ukrainians to understand that the situation is difficult, I urge them to be as prepared as possible for the fact that there will be no quick improvement in the situation with electricity.”

Police and investigators inspect a crater at a site of an industrial area destroyed by a Russian missile strike in Kharkiv.

Ukraine’s Armed Forces said Russia pounded the country with 76 missiles, launching cruise missiles from its fleets in the Black and Caspian Seas, and, for the first time, from Tu-95 strategic bombers at the Engels air base, on the Volga River in southern Russia.

The Engels air base, which is home to Russia’s long-range, nuclear-capable bombers, was targeted in a drone attack in early December, according to the Kremlin, slightly damaging two planes. Kyiv has not claimed responsibility for the attack.

An MiG-31K, a supersonic aircraft capable of carrying a Kinzal hypersonic missile, was also seen in the sky over Belarus during the air attacks on Friday in Ukraine, according to Ukraine’s Armed Forces. But it was not clear from their statement whether a Kinzal was used in the attacks.

“The enemy wanted to massively disperse the attention of air defense,” a spokesman for the Ukrainian Air Force, Yurii Ihnat, said. Ukraine’s top military chief, Valeriy Zaluzhny, later said that 60 of the missiles were downed by the country’s air defense forces.

Last Monday, Maj. Gen. Kyrylo Budanov, head of Ukraine’s military intelligence, claimed that Russia had nearly exhausted its arsenal of high-precision weapons, but that it still had enough supplies to inflict harm. He added that Iran has not delivered any ballistic missile to Russia – analysis echoed by John Kirby, spokesman for the White House National Security Council (NSC).

“We know that their defense industrial base is being taxed,” Kirby said of Russia. “We know they’re having trouble keeping up with that pace. We know that he’s (Russian President Vladimir Putin’s) having trouble replenishing specifically precision guided munitions.”

CNN is unable to verify the level of Russian missile stocks, which has previously been underestimated by Ukrainian officials.

The Biden administration is finalizing plans to send the Patriot, the US’ most advanced ground-based air defense system, to Ukraine, according to two US officials and a senior administration official. Ukraine’s government has long requested the system to help it defend against repeated Russian missile and drone attacks. It would be the most effective long-range defensive weapons system sent to the country and officials say it will help secure airspace for members of the North Atlantic Treaty and America (NATO) in eastern Europe.

In a press briefing on Friday, the White House condemned Russia’s strikes targeting largely civilian infrastructure. Kirby said that the attacks showed that Moscow was “again trying to put fear into the hearts of the Ukrainian people and to make it that much harder on them as winter is now upon them.”

He declined to announce any details on the next security assistance package for Ukraine, but said that there “will be another one” and that additional air defense capabilities should be expected.

The US and NATO countries have been grappling in recent months with how to help Ukraine defend itself against relentless Russian strikes, which have, according to Ukrainian officials, destroyed about half of the country’s energy infrastructure.

On Tuesday, about 70 countries and international organizations pledged more than $1 billion to help repair Ukraine’s infrastructure. Last week, the Pentagon announced that an additional $275 million in security assistance for Ukraine had been approved, including weapons, artillery rounds and equipment to help Ukraine boost its air defense. In November, the US announced a $53 million package to support repairs to Ukraine’s power system.

The “first tranche” of the energy-related equipment included in the US package has arrived in Ukraine, Kirby said Friday.

Olga Voitovych reported from Kyiv, and Eliza Mackintosh wrote in London. CNN’s Maria Kostenko, Victoria Butenko, Sebastian Shukla, Tim Lister and Betsey Klein contributed to this report.