Ukraine fires U.S.-made ATACMS missiles into Russia's Bryansk ...

Ukraine strikes Russia with U.S.-supplied missiles 02:24

Zhytomyr, Ukraine — Ukraine braced Wednesday for possible Russian retaliation after firing American-made and supplied missiles into Russia the previous day. The U.S. Embassy in Kyiv closed its doors on Wednesday and warned there were indications Russia was poised to launch a possible "significant air attack" on Ukraine.

Exactly 1,000 days after Russia launched its full-scale invasion of its neighboring nation, Ukrainian forces fired eight U.S.-made ATACMS missiles into Russian territory on Tuesday, U.S. officials have confirmed to CBS News. It was the first time Ukrainian forces had taken advantage of President Biden's easing of restrictions over the weekend on Ukraine's use of the U.S.-supplied missiles to strike targets deeper inside Russia.

Ukraine's military said it hit a Russian weapons depot in Bryansk early Tuesday, but it didn't say what weapons were used.

In the immediate wake of the strike on Bryansk, the U.S. Embassy in Kyiv warned Americans in Ukraine to exercise extra caution in the weeks ahead and to stockpile food. On Wednesday, the embassy followed up with a formal security alert saying it had "received specific information of a potential significant air attack" by Russia, possibly within hours. 

Ukrainian service personnel use searchlights to search for drones in the sky over Kyiv during a Russian drone strike, early on Nov. 20, 2024. Gleb Garanich/REUTERS

"Out of an abundance of caution, the Embassy will be closed, and Embassy employees are being instructed to shelter in place," the alert said, adding that U.S. nationals in the country should be "prepared to immediately shelter in the event an air alert is announced."

A Ukrainian military official told CBS News on Wednesday that the country had information suggesting the Russians could try to strike the center of Kyiv with ballistic missiles. Soon after, air raid sirens blared across Kyiv and other major cities, forcing thousands of people to seek shelter underground before the alert was lifted. 

An infographic shows the range and other details of the U.S.-made ATACMS missiles supplied to Ukraine. Murat Usubali/Anadolu/Getty

In a statement carried by state media, Russia's Defense Ministry said Tuesday the military had shot down five ATACMS fired by Ukraine and damaged another. The reports said fragments had fallen at or near a military facility and that some of the debris had ignited a fire, but the ministry said there was no damage or casualties. 

The U.S. officials told CBS News thatr Russia may have shot down two of the ATACMS launched by Ukraine in the strike.

The Ukrainian strike on Russia's western Bryansk region came hours after another Ukrainian residential neighborhood was left charred and smoking. Ukrainian officials said 10 people were killed Monday in a Russian drone and missile attack on the southern city of Odesa. That strike came a day after another strike on the power grid in Odesa, which also destroyed several homes.

With Mr. Biden finally granting Ukraine the long-sought permission to fire ATACMS — which have a range of about 190 miles — deeper into Russia, President Volodymyr Zelenskyy's forces had a new option to retaliate for the latest carnage.

People look at an apartment building hit by a Russian missile strike in Odesa, Ukraine, Nov. 18, 2024. Ukrinform/NurPhoto/Getty

Russia, however, has accused the U.S. of adding fuel to the fire. 

In September, President Vladimir Putin warned that if the U.S. allowed Ukraine to use ATACMS inside his country, it would mean the U.S. and its NATO allies were at war with Russia. 

Putin has yet to respond directly to Mr. Biden's weekend decision, but lawmakers in Moscow fumed over the move on Monday, including a senator who called it "a very big step toward the beginning of the third world war."

Oleksandra Ustinova, a member of Ukraine's parliament who says she helped lobby the U.S. government to let Ukraine use the ATACMS deep inside Russia, told CBS News the strike on Bryansk helped demonstrate "that these are legitimate targets, and that they're very important to protect our civilian population and our armed forces."

Mr. Biden only agreed to Ukraine's long-sought permission to fire ATACMS into Russia on Sunday. He had been worried that such a decision could escalate the conflict. 

But the Kremlin has appeared less concerned about stoking fears of an escalation. Putin formally approved a change in Russia's nuclear doctrine Tuesday, lowering the threshold for a potential nuclear strike. 

Ustinova, the Ukrainian lawmaker, was dismissive of the move. 

"He keeps playing and pretending like he's going to do something," she told CBS News. "I've been saying since day one that he's a bully, and he's not going to do that."

Russia and Ukraine have both kept their respective death tolls from the war secret, but Ukraine's military has undeniably paid a steep price for trying to defend the country from the invasion, with around 70,000 troops believed to have been killed. More than 100,000 soldiers from Russia — a country with a population more than three times larger than Ukraine's — have been killed, according to U.S. officials.

Russia condemns Biden's decision to let Ukraine fire missiles deep into Russia 02:18

Col. Maksym Balagura, a special forces commander in Ukraine's state border guard, acknowledged the vast size discrepancy when asked by CBS News if his country was short on manpower, saying it "isn't possible to compare Russia and Ukraine. … Their country is 10 times the size of ours, and of course they have more manpower."

But with the grueling ground and air war showing no signs of letting up, Russia's military has already been bolstered by more than 10,000 North Korean soldiers, according to Ukrainian, South Korean and U.S. officials.

Zelenskyy warned Tuesday that the North Korean contingent supporting Russia's forces could grow to 100,000 as the two Western adversaries deepen their security ties.

Charlie D'Agata contributed to this report.

In: War Nuclear Weapons Ukraine Russia Missile Launch Vladimir Putin Volodymyr Zelenskyy NATO