Preliminary information did not show any casualties in the attacks, the air force said on the Telegram messaging app.

Russia and Ukraine have increased their air attacks on each other’s territory in recent months, targeting critical military, energy and transport infrastructure.

The air force said Russia attacked the central Poltava region with two ballistic missiles fired from the Iskander ballistic missile system, and three surface-to-air missiles over the Donetsk region in the east.

Filip Pronin, governor of Poltava region, wrote on Telegram that the attack struck an industrial site in the city of Kremenchuk, sparking a fire. Pictures posted on social media showed emergency crews battling a blaze.

Further southeast in the Zaporizhzhia region, governor Yuri Malashko said an infrastructure site had been hit in a drone attack. Emergency crews were at the site, Malashko said, but gave no details of damage or casualties.

Ukraine’s air defence systems destroyed four of eight Russia-launched drones overnight, the air force said.

Reuters could not independently verify the reports. There was no immediate comment from Russia.