CNN
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Ukraine has fired US-made ATACMS missiles into Russia’s Bryansk region, the Russian Defense Ministry said, in a major escalation on the 1,000th day of the war.

The attack comes just two days after the Biden administration gave Kiev the green light to use U.S. weapons at longer ranges against targets in Russia.

Kiev did not immediately respond to the report. The attack marks the first time Ukraine has used longer-range US weapons to strike targets deep inside Russia, and shows that Kiev has wasted little time in using the newly granted powers.

At 3:25 a.m. local time (7:25 p.m. ET) on Tuesday, Ukraine fired six ballistic missiles at a facility in Bryansk, the ministry said. It said American-made ATACMS missiles were used in the attack.

Russian air defenses said they had shot down five of the missiles and that another was damaged. Fragments of the damaged missile fell on the territory of a military facility, causing a fire that has since been extinguished. There were no casualties or damage.

On Sunday, US President Joe Biden authorized Ukraine to use US missiles with longer range inside Russia, ending a months-long ban aimed at helping Ukraine defend itself without drastically escalating the conflict.

The decision came at a crucial moment in Russia’s invasion of Ukraine. Russia is probing the frontlines in eastern Ukraine as it bombards its cities with missile and drone strikes, aiming to knock out Ukraine’s power grid and weaponize freezing temperatures for a third straight winter.

Meanwhile, thousands of North Korean troops have been deployed to Russia’s Kursk region, where Ukrainian forces launched a daring counteroffensive this summer.

In a news conference Monday, U.S. State Department spokesman Matthew Miller said the involvement of North Korean forces in the war was “a major escalation by Russia, drawing an Asian military into a conflict within Europe.”

The decision to allow the use of the Army Tactical Missile Systems (ATACMS) in Russia had been under consideration for months. US officials were divided on the wisdom of allowing the new capability. Some were concerned about the escalation of the war, while others worried about dwindling weapons supplies.

While Kiev has repeatedly used Ukrainian-made drones to hit targets in Russia — deeper into the country than Bryansk — Moscow has long maintained that using far-reaching Western weapons would represent a major escalation.

Following the reported missile attack early Tuesday morning, President Vladimir Putin updated Russia’s nuclear doctrine — just two days after Biden’s green light.

According to the updated doctrine, Moscow will consider aggression by any non-nuclear state – but with the participation of a nuclear country – as a joint attack on Russia.

However, in the more than two and a half years of war, Russia has often used nuclear weapons in response to perceived escalation by Ukraine and its allies.

After French President Emmanuel Macron said earlier this year that he would not rule out sending European troops to Ukraine, Putin ordered a tactical nuclear weapons exercise in response to what he called “threats” from the West.

For months, Ukrainian President Volodymyr Zelensky had argued that “long-range capabilities for our military” are an important part of his “Victory Plan” for winning the war.

Responding to reports of Biden’s green light, Zelensky said on Sunday evening: “Strikes are not carried out with words. Such matters are not announced. Missiles will speak for themselves.”