The U.S. has uncovered "credible information" that Russian forces "are creating lists of identified Ukrainians to be killed or sent to camps," and that Russian troops will "likely use lethal measures to disperse peaceful protests," according to a recent letter to a U.N. high commissioner, sent by a U.S. ambassador.

The undated letter—published by The Washington Post on Sunday and written by Ambassador Bathsheba Nell Crocker, U.S. representative to the Office of the United Nations, and addressed to U.N. High Commissioner for Human Rights Michelle Bachelet—warns of a potential "human rights catastrophe" in the coming days.

"I would like to bring to your attention disturbing information recently obtained by the United States that indicates that human rights violations and abuses in the aftermath of a further invasion are being planned," Crocker wrote. "These acts ... would likely target those who oppose Russian actions, including Russian and Belarusian dissidents in exile in Ukraine, journalists and anti-corruption activists, and vulnerable populations such as religious and ethnic minorities and LGBTQI+ persons

The Russian-held Kherson International Airport and Air Base near the southern Ukrainian port city has successfully been struck by Ukrainian forces, according to a number of satellite images.

The Ukrainian attack on Tuesday appears to have destroyed a number of Russian helicopters, with images obtained by Planet Labs PBC showing a cloud of thick, black smoke rising from burning helicopters.

The first image shown above—the one in color—was taken at 1:35 p.m. local time on March 15, 2022.

The satellite images appear to show at least three helicopters on fire, as well as several vehicles. At a pad further away, other helicopters appeared to have been damaged by an earlier strike.

In rare backing for Russia following its invasion of Ukraine, Venezuela's President Nicolas Maduro on Tuesday assured Vladimir Putin of his "strong support" in a telephone call, according to a Kremlin statement.

In the call initiated by Caracas, the Venezuelan leader also condemned "destabilizing actions of the United States and NATO" and spoke out against a Western campaign of "lies and disinformation," it said.

Dozens of people have been killed and nearly 680,000 have fled Ukraine since Putin ordered his troops into the country last week after failing to get guarantees that NATO will not expand its military alliance eastward.

In the call with Maduro, Putin insisted the objectives of the military assault were to "protect the civilian population" of the Donbass separatist region and to get Kiev to recognize Russian sovereignty over Crimea, which it annexed in 2014.