MOSCOW >> Ukraine struck a major Russian strategic bomber airfield on Thursday with drones, triggering a huge blast and fire about 700 km (435 miles) from the front lines of the war, Russian and Ukrainian officials said.

Videos verified by Reuters showed a huge blast spreading out from the airfield, wrecking nearby cottages. Russia’s defense ministry said air defenses had shot down 132 Ukrainian drones over Russian regions.

Other verified videos showed a giant plume of smoke rising into the dawn sky and an intense fire.

The base in Engels, which dates back to Soviet times, hosts Russia’s Tupolev Tu-160 nuclear-capable heavy strategic bombers, known unofficially as White Swans.

Roman Busargin, governor of Saratov, said there had been a Ukrainian drone attack on the city of Engels that had left an airfield on fire, and that nearby residents had been evacuated. He did not specifically mention the Engels base, but it is the main airfield in the area.

Ukraine’s defense ministry said its forces had struck the airfield and triggered secondary detonations of ammunition. Kyiv said Russia had used the Engels base to carry out strikes on Ukraine.

Ten people were injured in the attack, local officials said. Some local residents expressed surprise at finding various parts of Ukrainian drones in their gardens. The Shot Telegram channel said that Ukraine struck with PD-2 and Liutyi drones.

Engels district head Maxim Leonov said that a local state of emergency had been declared but gave few details. Reuters was unable to independently confirm what had taken place at the airfield.

Ukraine has conducted previous attacks on the Engels air base dating back to December 2022. In January it claimed to have struck an oil depot serving the base, causing a huge fire that took five days to put out.

A Ukrainian security source said at the time that a drone attack had struck a storage facility holding guided bombs and missiles at the Engels base.