The Russian Defense Ministry said its troops were in the center of the city of Kherson after conflicting claims over whether Russian soldiers had captured a major urban center for the first time in its eight-day invasion.
Kherson Mayor Igor Kolykhayev said late on Wednesday that Russian troops were in the streets and had entered the council building.
"The occupiers are in all parts of the city and are very dangerous," Gennady Lakhuta, head of the regional administration, wrote on messaging service Telegram late Wednesday
US Congress passes resolution in support of Ukraine
The US House of Representatives approved a resolution "steadfastly, staunchly, proudly and fervently" in support of Ukraine. Many in Congress urged that more be done to stop Russian President Vladimir Putin's war of aggression against Ukraine.
Only three members of the House voted against the resolution: Republicans Paul Gosar of Arizona, Thomas Massie of Kentucky and Matt Rosendale of Montana.
US Senator Lindsey Graham, a Republican from South Carolina, is introducing a similar resolution in the Senate, the upper chamber.
On Tuesday night, members of both political parties in the US wore pins and waved the sky blue and sunflower yellow of the Ukrainian flag during US President Joe Biden's State of the Union address to both chambers.
Air raid sirens in Kyiv
Residents of the Ukrainian capital were told to go to the nearest shelter early Thursday morning. Videos shared on social media showed explosions hitting the city.
More than 1 million refugees flee Ukraine
The UN high commissioner for refugees, Filippo Grandi, said more than 1 million people have fled Ukraine.
Grandi tweeted, "In just seven days we have witnessed the exodus of one million refugees from Ukraine to neighboring countries."
The 1 million figure amounts to the displacement of more than 2% of Ukraine's population. As of 2020, World Bank figures showed Ukraine had a population of 44 million.
The UNHCR predicts up to 4 million people could make an exodus out of Ukraine, though with the caveat that this figure too could increase.
At this rate, UNHCR spokesperson Shabia Mantoo said that "at this rate" Ukraine could experience "the biggest refugee crisis this century."
UN records 752 civilian deaths in Ukraine
The UN Office of the High Commissioner of Human Rights (OHCHR) monitoring mission in Ukraine said it had recorded 752 deaths among Ukrainian civilians since the conflict began at 4 a.m. (0300 GMT) on February 24. An additional 525 have reportedly been injured during the war.
In a statement, the monitoring mission noted, "This is more than the total number of civilian casualties recorded by OHCHR in the conflict zone of eastern Ukraine from 2018-2021," when 136 people were killed.
"Most of these casualties were caused by the use of explosive weapons with a wide impact area, including shelling from heavy artillery and multi-launch rocket systems, and airstrikes," the UN body said.
The statement added that the UN "believes that real figures are considerably higher, especially in Government-controlled territory and especially in recent days, as the receipt of information from some locations where intensive hostilities have been going on was delayed and many reports were still pending corroboration."