Updated with new death toll.
Overnight Russian air strikes against Ukraine's second-largest city Kharkiv killed at least five people and injured one dozen others, Ukrainian officials said Thursday.
Three rescue workers died during a second strike on a residential building in a "densely populated district of Kharkiv," Kharkiv Mayor Ihor Terekhov said on the messaging app Telegram.
Another person died in a drone attack on a separate building, he said. Police described the fourth victim as a 68-year-old woman and said 11 people had been injured in the overnight attacks.
Russian forces also targeted power infrastructure, killing a 47-year-old energy worker in an aerial bomb attack on the neighboring Sumy region, the Energy Ministry said.
Kharkiv region Governor Oleh Syniehubov said Russian forces had launched "at least 15 drones," some of which had been downed by air defense systems.
Ukrainian cities are targeted by Russian strikes nearly every night, with Kharkiv, which is located near the northeastern border with Russia, among those most frequently attacked.
Officials in Kyiv have urged Western allies to supply more anti-aircraft defense systems, in particular modern U.S.-made Patriot systems.
American military aid to Ukraine has been drying up in recent months, with a $60-billion funding package currently stalled in Congress.
