KYIV, Oct 17 - Waves of explosives-laden suicide drones struck Ukraine’s capital Monday, setting buildings ablaze, tearing a hole in one of them and sending people scurrying for cover or trying to shoot them down in what the president said was Russia’s attempt to terrorize civilians.

The concentrated use of the kamikaze drones was the second barrage in as many weeks — after months in which air attacks had become a rarity in central Kyiv, The Associated Press reported. Energy facilities were struck and one drone largely collapsed a residential building, killing four people, authorities said.

Previous Russian airstrikes on Kyiv were mostly with missiles. Analysts believe the slower-moving Shahed drones can be programmed to accurately hit certain targets using GPS unless the system fails.

Also Monday, a Russian Su-34 warplane crashed in a residential area in the Russian port of Yeysk, on the Sea of Azov, after an engine failure — killing at least four people on the ground, injuring 25 others and starting a fire that engulfed several floors of a nine-story apartment building, authorities said.

Vice governor of the region, Anna Menkova, said three of the victims died when they jumped from the building’s upper floors to escape the flames, according to the RIA-Novosti news agency. Six more people were missing.

In Kyiv, Mayor Vitali Klitschko said Monday’s barrage came in successive waves of 28 drones — in what many fear could become a more common mode of attack as Russia seeks to avoid depleting its stockpiles of long-range precision missiles.

Five drones plunged into Kyiv itself, said Prime Minister Denys Shmyhal. In the Kyiv region, at least 13 were shot down, all flying in from the south, said Yurii Ihnat, a spokesman for Ukraine’s air force.

One strike appeared to target the city’s heating network, hitting an operations center. Another slammed into a four-story residential building, ripping open a gaping hole and collapsing at least three apartments. Four bodies were recovered, including those of a woman who was 6 months pregnant and her husband, Klitschko said. An older woman and another man also were killed there.

“The whole night, and the whole morning, the enemy terrorizes the civilian population,” President Volodymyr Zelensky said in a social media post. “Kamikaze drones and missiles are attacking all of Ukraine.”

In a televised address to the nation Monday night, Zelenskyy said Moscow was resorting to the drones because it was losing the war.

“Russia doesn’t have any chance on the battlefield, and it tries to compensate for its military defeats with terror,” he said. “Why this terror? To put pressure on us, on Europe, on the entire world.”

Zelensky, citing Ukrainian intelligence services, alleges Russia ordered 2,400 drones from Iran. Russia has rebranded them as Geran-2 drones — “geranium” in Russian. A photo of debris from one of Monday’s strikes, posted by Klitschko, showed “Geran-2” marked on a mangled tail fin.

EU foreign policy chief Josep Borrell said the 27-nation bloc is gathering evidence about Iran’s drone sales to Russia, and if true, “we will be ready to react with the tools at our disposal.” The EU also approved a military training program in Europe for thousands of Ukrainian troops and plans for about 500 million euros ($486 million) in extra funds to buy weapons for Ukraine.

Iranian-made drones have been used elsewhere in Ukraine in recent weeks against urban centers and infrastructure, including power stations. At just $20,000 apiece, the Shahed is only a fraction of the cost of higher-tech missiles and conventional aircraft. The Kalibr cruise missile that Russia has used widely in Ukraine costs the military about $1 million each. (ap/ez)