Russia air defence units destroyed nine Ukrainian drones heading towards Moscow by 4am, mayor Sergei Sobyanin said on the Telegram messaging app.

Emergency services were dispatched to the sites where drone debris fell in the overnight attack, Sobyanin said. He did not report any immediate damage.

A Ukrainian drone attack also sparked a short-lived fire at the Azot chemical plant in the Tula region, injuring two people, and seven drones were destroyed over the Kaluga region, regional governors said.

Both regions border the Moscow region to the south of the capital.

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

Russia’s civil aviation authority Rosaviatsia said on Telegram that to ensure air safety it was halting flights at the Vnukovo and Domodedovo airports.

Russia and Ukraine have increased their attacks in recent weeks while also returning to peace talks for the first time since the early days of the war that Russia launched against Ukraine in February 2022.