Millions of children inside Ukraine and those fleeing to neighboring countries are at risk of hypothermia, hunger and death, as temperatures could dip below -4 degrees Fahrenheit, non-profit group Save the Children said Friday.

Eastern Europe, including Ukraine, was hit with an "extreme Arctic cold blast" this past week, according to Save the Children

"As temperatures plummet, children who have been forced from their homes are trekking through the brutal cold, with high winds and snow, carrying whatever they could grab before they fled," said Irina Saghoyan, Save the Children’s Eastern Europe director.

-ABC News' Zoe Magee

Russian forces claim the Ukrainian power plant Zaporizhzhia belongs to Russia's state atomic agency, Rosatom, the head of Ukraine's nuclear energy company, Energoatom, said Friday on Ukrainian TV.

Russian forces took control of the Zaporizhzhia region last week.

Energoatom’s chief Petro Kotin said that officials from the Russian agency, backed by the 500 Russian troops surrounding it, tried to enter the plant and take control of it this week.

-ABC News' Patrick Reevell

A senior administration official told ABC News Friday that the U.S. is getting reports the Russians are starting to bring in biochemical weapon suits into Ukraine.

The reports comes as the Russians accuse Ukraine and the U.S. of developing biochemical weapons, which the U.S. has denied.

"We believe it is an ominous sign they are possibly doing it for cover," the official said.

According to the official, as much as one-fifth of the Russian force is currently "inoperable," meaning they are either dead, wounded or do not have the support or equipment needed to continue.

But even though the Russians are bogged down they realize that everything depends on taking Kyiv and continue to put all effort into that, according to the official.

There are also concerns about boxing Putin in as well as his consistent and casual mention of nuclear weapons. According to the official, that is one of the reasons he has not been publicly labeled as a war criminal because "we just don't know what he will do."

-ABC News' Martha Raddatz

White House Deputy Press Secretary Andrew Bates fell short of calling Putin’s actions in Ukraine war crimes despite acknowledging that that evidence is mounting that Russia’s attack in the country will result in war crimes on Friday.

“We've all seen the devastating images coming out of Ukraine and are appalled by Russia's brutal tactics. Pregnant women on stretchers, apartment buildings - buildings shelled, families killed while seeking safety from this terrible violence,” Bates said while briefing reporters aboard Air Force One.

"These are disgusting attacks, civilian casualties are increasing. If Russia is intentionally targeting civilians, that would be a war crime," he said.

Bates said the administration would share any evidence that is collected with its allies and hinted that it expects evidence will show that war crimes are being committed.

“If Russia is intentionally targeting civilians, that would be a war crime and as we are all seeing on live television evidence is mounting, and we are documenting it as it takes place," Bates said.

-ABC News' Armando Tonatiuh Torres-García