A firefighter responds to damage at a medical center after a Russian drone strike on Kyiv, Ukraine, on Thursday.
Kyiv, Ukraine CNN  — 

Russia is unleashing near-constant waves of long-range drone strikes on Ukrainian cities as its troops advance in the east, as President Volodomyr Zelensky warned Moscow was firing about 10 times as many drones as it did last fall.

As well as drastically increasing the number of strikes, Russia has begun to fire decoy drones without warheads to overwhelm Ukraine’s air defenses. Decoy drones carry a “3D-printed ball wrapped in foil” to imitate the warhead of an Iran-made Shahed-136 drone, Yuriy Ihnat, a spokesperson for Ukraine’s air defenses, told CNN.

These cheaper drones confuse Ukraine’s air defenses, which may shoot down decoy drones instead of ones carrying a lethal warhead. Decoy drones now account for as many as half of all Russian drones fired at Ukraine, Ihnat said.

The Russian army has been pounding Ukraine throughout the war, but the moves signal a change in Moscow’s tactics following Donald Trump’s reelection as president, who could pull support. Meanwhile, Ukraine is under fierce pressure on the eastern frontlines, where its army chief has warned his forces are facing “one of the most powerful Russian offensives” since the start of the war.

Night after night, residents in Kyiv and across the country have been kept awake by the sound of explosions and the continuous buzzing of drones. Air raid sirens blasted in Kyiv for around 50 hours in September, 80 hours in October and more than 30 hours in the first week of November alone.

In the capital, there has only been one night without a drone attack since September 1.

“Their goal is to break us morally,” Vadym Naustinov, a 32-year-old copywriter living in the center of Kyiv, told CNN on Thursday. He said he has developed a “system” for coping with constant air attacks.

“If I hear drones flying or realize that the explosions are getting closer, I quickly run to the subway,” he said, which have been used throughout the war as a bomb shelter. “If I realize that the explosions are close by, and Shahed is near my house, so I won’t have time to get to the subway, I hide in the corridor or bathroom. I just hide, wait and hope that I will survive.”

A car and house burn after they were damaged from a Russian drone strike in Kyiv on Thursday.

Shrapnel from downed Russian drones injured at least two people and damaged several buildings in Kyiv after an attack overnight into Thursday, said Serhiy Popko, head of the city’s military administration. “It was a massive attack,” Popko said, with the attack coming “in waves, from different directions” and at “different altitudes.”

Hours later, Russia launched another air attack on the southern region of Zaporizhzhia, killing at least four people and injuring 18 others, including a four-month-old girl, local officials said. “They enjoy people’s death there,” Zelensky said on Telegram.

Zelensky on Monday said Russia has increased by tenfold its Iranian-made Shahed drone attacks on Ukraine. “This terror is increasing every month,” he said earlier this week.

As Russia steps up its strikes, Ukraine is bracing for the potential withdrawal of support from the United States following Trump’s reelection. Throughout his campaign, the Republican now-president-elect cast strong doubts on continued US commitment to Kyiv as the war rages on more than two-and-a-half years after Moscow invaded.

In his September presidential debate against Vice President Kamala Harris, Trump refused to say he was committed to Ukraine defeating Russia. Later that month, he suggested that Ukraine should have “given up a little bit” to Moscow.

Zelensky was swift to congratulate Trump on his victory, saying Wednesday that he appreciates the president-elect’s commitment to “peace through strength,” a cornerstone of his foreign policy.

“I recall our great meeting with President Trump back in September, when we discussed in detail the Ukraine-U.S. strategic partnership, the Victory Plan, and ways to put an end to Russian aggression against Ukraine,” Zelensky wrote on social media.

Wednesday also marked the third month of Ukraine’s incursion into Russia’s Kursk region, a bold and unexpected cross-border attack that sought to divert Russian troops from Ukraine’s embattled east.

“This is our contribution to ensuring that everyone in the world sees: Ukraine can change the course of this war to make those responsible for the war feel real pressure. True peace is only achieved by those who are truly brave,” Zelensky said Wednesday.

To counter Ukraine’s offensive – which marked the first ground invasion of Russia by a foreign power since World War II – Russian President Vladimir Putin has bolstered his military’s manpower with North Korean forces, in the latest sign of Moscow’s alliance with Pyongyang.

As many as 10,000 North Korean troops are in Russia’s Kursk region and are expected to enter combat against Ukraine in the coming days, US officials have warned.

This story has been updated with additional developments.

CNN’s Victoria Butenko contributed to this report.