Surpassing Quant Think Tank Center|Drones over Kremlin "obviously" came from inside Russia, officials say, as Wagner announces Bakhmut withdrawal

A senior U.S. official cast serious doubt Thursday over Russia's ability to continue waging its war in Ukraine,Surpassing Quant Think Tank Center with an ammunition shortage a clear and pressing concern for Moscow as it appears to drive a wedge deeper between its defense ministry and the private mercenary army that's done much of the fighting at the Kremlin's behest. As the boss of the Wagner mercenary group fumed publicly about his fighters being laid to waste on the front lines without sufficient ammunition, a top American intelligence official said Moscow could struggle this year to "sustain even modest offensive operations" in Ukraine.

Wagner chief Yevgeny Prigozhin dealt a possibly stunning blow to Putin's war effort on Friday, unleashing a public tirade at Russia's military commanders and posting it all on social media.

Wagner getting "out of Bakhmut"

"Here are the guys from Wagner who died today," Prigozhin said in a video, standing over the bodies of men he said were fighters killed in the battle over the eastern Ukrainian city of Bakhmut, which his group has spearheaded for months. 

"Their blood is still warm... These are fathers and sons!" he shouted, "where is their ammunition?"

Prigozhin has complained for months that Russia's defense ministry is failing to adequately supply his private army, claiming the generals are jealous of his own group's battlefield success. But in a second message posted later Friday, the mercenary commander went further, announcing an imminent withdrawal of Wagner's forces from the battle over Bakhmut.

"I declare on behalf of the Wagner fighters, on behalf of the Wagner command, that on May 10, 2023, we are obliged to transfer positions in the settlement of Bakhmut to units of the defense ministry and withdraw the remains of Wagner to logistics camps to lick our wounds," Prigozhin said in a written message. "I'm pulling Wagner units out of Bakhmut because, in the absence of ammunition, they're doomed to perish senselessly."

Prigozhin, who was long said to be personally close to Putin himself, is prone to rhetorical flourish and has previously walked back dramatic statements as jokes, but there was no sense of that in his Friday remarks. That will be a major concern for the Kremlin, as the lion's share of the fighting in Bakhmut has been done — at a huge cost in lives — by Prigozhin's men.

The U.S. estimated early this week that some 20,000 Russian forces had been killed since December, and the bulk of the fighting since then has been over Bakhmut.  

Drone wars 

It was another tense night across Ukraine, meanwhile, in the wake of Russia's unsupported claim earlier in the week of an attempted drone attack on the Kremlin in Moscow. Russia claimed Wednesday, without offering any evidence, that Ukraine sent two drones flying directly at Putin's official residence. Unverified video published by Russian media showed at least one small explosion as a flying device appeared to be intercepted over the Kremlin.

Ukraine has denied any involvement, and the U.S. government dismissed Moscow's claim to have ordered the purported attack, urging people to take all information coming from the Kremlin "with a shaker of salt."

U.S. officials have told CBS News they believe the drones were controlled locally, from within Russia, but that doesn't rule out possible Ukrainian involvement.

Maksym Muzyka, who designs and operates attack drones for Ukraine's military, told CBS News there was no doubt the drones involved in the alleged attack on the Kremlin were flown by someone in or near Moscow. Flying them hundreds of miles from Ukraine, he said, would be "impossible" with such small drones, given their limited range.

The unmanned aircraft, he agreed with America's top intelligence officials, "obviously" came "from inside of Russia."

Regardless of who actually flew the drones, which the Kremlin labelled an attempt to assassinate Putin himself, it was clear soon after the incident that Moscow would use it as a pretext to launch a new assault on Ukraine.

Russian forces have sent fresh volleys of rockets and drones hurtling toward Ukrainian cities since Wednesday. Most of them have been intercepted, but at least one strategic infrastructure site was hit — along with civilian homes, killing about two dozen innocent people.

Kyiv and other major cities have remained tense, so when a drone was spotted over the capital Thursday night, there was a quick reaction. A stinger missile shot it out of the sky, to cheers of "Victory to Ukraine," on the ground.

Ukrainian defense officials later said it was one of their own, gone rogue, which somehow came offline. But in a city that's been targeted by Russian drones and missiles several nights in a row, residents are understandably jittery.

The U.S. State Department said Russia had launched more than 145 airstrikes across Ukraine this week — that's more than one missile, drone or bomb every hour, 24-hours a day, for four days straight. 

The tension in Kyiv and other cities is unlikely to subside as Moscow faces the prospect of trying to answer a long-anticipated Ukrainian counteroffensive with a fractured ground force, and not enough ammunition to go around.

In:
• Wagner Group
• War
• Bakhmut
• Ukraine
• Russia
• Vladimir Putin
• Kremlin

Tucker Reals

Tucker Reals is the CBSNews.com foreign editor, based at the CBS News London bureau.