KYIV, Ukraine - Explosions rocked cities across Ukraine early Thursday morning, as Russia continued its unrelenting pummeling of the country's energy infrastructure, launching dozens of missiles and hospitalizing at least three people in the capital, Ukrainian officials said.

Air raid sirens sounded out across Ukraine at 6 a.m. Washington Post journalists heard the first of several explosions in Kyiv a little over an hour later. Local officials in Odessa in the south, Kharkiv in the east, Lviv in the west and other regions reported missile attacks on social media. It was not immediately whether the sounds of blasts were from strikes or air defenses.

"The enemy attacks Ukraine from various directions with air and sea-based cruise missiles from strategic aircraft and ships," Ukraine's Air Force said in a statement on Telegram, calling it a "massive missile attack."

Moscow has pounded Ukraine's infrastructure since early October, in an effort to leave the country without light, heat and water during the freezing winter months and weaken the Ukrainians' resolve to continue the war effort - a strategy that so far seems to have failed considerably.

It was the first major missile attack in about two weeks - and just two days before the New Year's holidays. Russian forces also launched an assault of self-destructing drones on Ukrainian energy facilities last week.

Wire photos showed rescuers rushing to inspect the damage in Kyiv and residents taking shelter in a subway station.

Mykhailo Podolyak, an adviser to Ukrainian President Volodymyr Zelensky, tweeted that "the evil Russian world" had launched more than 120 missiles on Thursday "to destroy critical infrastructure and kill civilians en masse." Another official, Oleksiy Arestovych, said that more than 100 missiles were incoming "in several waves."

Ukraine's military said that some 69 missiles had been fired, of which 54 were intercepted by the country's air defense systems. The Washington Post could not independently verify any of the figures cited by Ukrainian officials.

Kyiv Mayor Vitaly Klitschko said on his Telegram channel that Ukrainian air defense forces had shot down 16 Russian missiles in the capital, while Odessa Gov. Maksym Marchenko said 21 missiles had been destroyed in his region.

But the missiles also caused extensive damage and injuries. Klitschko said that missile fragments struck a residential home, and three people, including a 14-year-old girl, had been injured in the capital. After the attack, 40 percent of Kyiv residents were without power, Klitschko said, though heat and water were continuing "as usual."

Head of the Kyiv Military Administration Serhiy Popko said that three districts in the capital had been hit, including a "industrial facility" and a children's playground. Governor of the Kyiv region Oleksiy Kuleba said during a television broadcast that a number of houses and a medical facility had been damaged outside of the capital during the attack, which lasted five hours.

Lviv Mayor Andriy Sadovyi reported that 90 percent of his city was without electricity after explosions. Odessa Gov. Marchenko said that missiles had struck "energy infrastructure" and that emergency blackouts were taking place across the region.

In Kyiv, one of the missiles shot down landed on Oleksandr Fatkulin's home, leaving half of the brick house in ruins. Oleksandr had been sleeping on the second floor while his elderly father, Leonid, was on the first.

"Are you alive?" Leonid said he yelled up to his son after the explosion ripped through the walls.

Hours later, both men watched as firefighters put out the last embers still burning from their home. Oleksandr took a video of the scene on his phone. Both father and son were luckily unharmed because they had been on the far side of the house that sustained less damage.

"I was about to take a shower when it happened," Leonid said. "Now I'm going to need someone to let me take a shower at their place."

Shrapnel from the missile was laid out neatly on the side of the road, piece by piece. A woman walked by with another piece - it had shattered the window of her home nearby.

"Is that another keepsake from Putin?" a neighbor asked her.