KYIV, Ukraine — Infrastructure in the region around the Ukrainian capital was attacked by kamikaze drones on Thursday, officials in Kyiv said.

The explosions occurred in the early morning in the town of Makariv, west of the capital, Kyiv Region Police Chief Andriy Nebitov said, adding that officers and rescue workers were on the scene.

Deputy head of the presidential office Kyrylo Tymoshenko said on Telegram that “critical infrastructure facilities” had been the target.

There was initially no word on possible casualties or details on what was struck.

As Moscow’s forces struggle on the battlefield, Ukraine has for weeks been reporting increased Russian attacks using the unmanned Iranian-made drones that operators smash into their target.

Experts from the U.S.-based Institute for the Study of the War reported that Russia brought Iranian instructors to the occupied territories of Ukraine to teach Russian troops how to use the drones.

For months, Kyiv and the surrounding area had been spared from the Russian military campaign largely centred on the south and east of Ukraine. But the capital came under heavy assault at the start of the week.

Heavy attacks also rocked the southern Mykolaiv region overnight. According to Governor Vitaliy Kim, a five-story apartment building was hit. At least two people were injured, including an 11-year-old boy who was rescued from the rubble after an operation lasting hours.