Russian air defenses intercepted 660 Ukrainian drones in a major nighttime attack on 12 Russian regions as well as the Russia-held Crimean peninsula, the Black Sea and the Azov Sea, Russia’s Defense Ministry said Friday.

It appeared to be one of the biggest drone attacks on Russia and the illegally annexed Crimea since Russia’s full-scale invasion of Ukraine more than four years ago. The previous biggest Ukrainian attack over the past year was 556 drones on May 17.

In an effort to turn the tables on Russia’s grinding war of attrition, Ukrainian long-range drones have for months been battering targets, including oil production and energy facilities, behind the front line and deep inside Russia.

The campaign has choked Russian fuel supplies and military deliveries, stalling Russia’s efforts on the battlefield, Western officials and analysts say, and heaped pressure on Russian President Vladimir Putin.

Initial damage reports from Russia after the overnight attack provided scant information. Russia’s Defense Ministry usually doesn’t say what was targeted in Ukraine’s drone attacks, nor does it detail any damage.

Successful drone attacks hearten Ukraine

The major attack came hours after Ukrainian President Volodymyr Zelenskyy said on X that he had ordered “a 40-day influence operation,” believed to mean an escalation of attacks, aimed at “compelling (Russia) to end the war” after US peace efforts over the past year yielded no breakthrough.

The successful strikes, including hitting targets in Moscow and St. Petersburg, have buoyed Ukraine.

Zelenskyy said he got further promises of foreign support when he attended a recent summit of G7 leaders, including from US President Trump, and that the promised aid will help Ukraine step up its effort to force Putin to the negotiating table.

A NATO summit next month could be another key moment in beefing up Ukraine’s military.

A Russian chemical plant is reportedly hit

In the Tula region just south of Moscow, a private house was damaged by the attack and a woman was wounded, Tula Gov. Dmitry Milyaev said in an online statement as reports of damage caused by the attack began to emerge.

He also said a power line was damaged and an unspecified industrial facility in the city of Novomoskovsk.

Russian independent online outlet Astra reported that a chemical plant and a hydroelectric plant in Novomoskovsk were attacked and caught fire. The Associated Press couldn’t independently verify the report, and there was no official confirmation.

Moscow Mayor Sergei Sobyanin also reported that 47 Ukrainian drones were downed as they flew toward the Russian capital. He did not report any casualties or damage.

Ukraine says 2 civilians were killed in Russian attacks

Two people were killed and seven others injured in Russian attacks on the northeastern Kharkiv region over the previous 24 hours, regional head Oleh Syniehubov said Friday.

Russian forces struck the city of Kharkiv and 16 other settlements across the region using guided aerial bombs and drones of various types, Syniehubov said.

Ukraine’s Defense Forces overnight stopped 174 of 189 Russian drones, the Ukrainian air force said. However, four of seven Iskander-M ballistic missiles that were fired got through air defenses and struck various locations, it said.

Ukrainian officials reported damage to energy facilities, homes and other civilian infrastructure in the capital, Kyiv, the southern Odesa region and Sumy in the northeast.