According to a Russian-installed official, an ammo stockpile was struck during a Ukrainian drone strike on Dzhankoi in Crimea early Monday, with Russian air defense forces shooting down or electronically jamming 11 drones over the region.

Sergei Aksyonov, the Russian-installed governor of Crimea, which Moscow invaded from Ukraine in 2014, also stated that a residential structure in the vicinity had been destroyed.

He said there was no indication of any casualties, but people within a 5 km (3 mile) radius of the incident were being evacuated.

It was not immediately clear whether the ammunition depot was directly hit by a drone or if it was damaged by falling drone debris.

Russia has a military air base near Dzhankoi. Ukrainian officials have long said the city and surrounding areas have been turned into Moscow’s largest military base in Crimea.

Aksyonov also said on the Telegram messaging app that “for safety reasons” railway and road traffic in the area was suspended.

Reuters could not independently verify the reports of the attacks. There was no immediate comment from Ukraine on the alleged attack.

Ukraine rarely publicly claims responsibility for attacks inside Russia or on Russian-controlled territory in Ukraine, but has been saying in recent months that destroying Russia’s military infrastructure helps Kyiv’s counteroffensive.

It was the second such attack in three days in Crimea. On Saturday, Aksyonov said a drone caused an explosion at an ammunition depot in central Crimea, prompting authorities to evacuate nearby people and briefly suspend road traffic on the bridge linking the peninsula to Russia.

Ukraine did claim that incident, saying its army had destroyed an oil depot and Russian army warehouses.