Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty in speech denouncing West

Ukraine's prosecutor general launched an investigation after a video emerged on social media of the Kremlin claiming Russian soldiers were killed after surrendering to Ukrainian forces.

Ukraine claimed Russia staged the attack, but Ukrainian authorities said they will investigate.

The videos, verified by the New York Times as authentic, have been circled online and in Ukrainian and Russian media show moments before and after a group of at least 11 Russian troops were killed by Ukrainian fighters after one of their fellow fighters suddenly opened fire on Ukrainian soldiers standing nearby.

The Ukrainian prosecutor general said law enforcement opened the criminal case "after Russian occupiers pretended to give up and then opened fire on fighters of the Armed Forces of Ukraine," according to a statement.

-ABC News' Will Gretsky

Ukrainian President Volodymyr Zelenskyy claimed Ukrainian forces have liberated over 1,800 settlements that were occupied by Russian forces. Zelenskyy claimed that more than 3,700 settlements have been occupied, he said in an address Tuesday.

Zelenskyy claimed that Russian soldiers mined and looted everything they could, leaving behind hundreds of thousands of buildings destroyed or damaged by shelling.

-ABC News' Will Gretsky

Russia's eroding situation could lead Russian President Vladimir Putin to "more nuclear saber-rattling," U.S. Defense Secretary Lloyd Austin warned Saturday.

"The ripples of Russia’s invasion has traveled far beyond Europe. Beijing, like Moscow, seeks a world where autocrats can stamp out the flame of freedom," Austin said while addressing the Halifax International Security Forum.

Austin said the deadly explosion in Poland this week was the result of the "recklessness of Putin’s war of choice."

"Russia’s invasion offers a preview of a possible world of tyranny and turmoil that none of us would want to live in. And it’s an invitation to an increasingly insecure world haunted by the shadow of nuclear proliferation," Austin said.

He went on, "Putin’s fellow autocrats are watching and they could well conclude that getting nuclear weapons would give them a hunting license of their own. And that could drive a dangerous spiral of nuclear proliferation."

-ABC News' Matt Seyler

An investigation into the cause of a leak from the Nord Stream pipelines in the Baltic Sea revealed "extensive damage" and several "foreign items," some with detectable "explosive residue," the Swedish Security Service and a prosecutor said Friday.

"The advanced analysis work is still in progress – the aim is to draw more definitive conclusions about the Nord Stream incidents. The investigation is extensive and complex and will eventually show whether anyone can be suspected of, and later prosecuted for this," prosecutor Mats Ljungqvist and the Swedish Security Service said in a statement.

Several blasts near the Nord Stream 1 and Nord Stream 2 gas pipelines on Sept. 26 caused leaks. Officials are still investigating the cause of the blasts. Major pipelines which supply natural gas from Russia to Europe, were shut off in September. While they were not in use at the time of the blast, the pipelines were filled with natural gas.

-ABC News' Will Gretsky