Russian President Vladimir Putin's "special military operation" into neighboring Ukraine began on Feb. 24, with Russian forces invading from Belarus, to the north, and Russia, to the east. Ukrainian troops have offered "stiff resistance," according to U.S. officials.
The Russian military has since launched a full-scale ground offensive in eastern Ukraine's disputed Donbas region, capturing the strategic port city of Mariupol and securing a coastal corridor to the Moscow-annexed Crimean Peninsula.
A look at the two leaders at the center of the war in Ukraine and how they both rose to power, the difference in their leadership and what led to this moment in history.
Here's how the news is developing. All times Eastern.
Apr 18, 2022, 4:45 PM EDT
US still assessing Russian strike in Lviv: Kirby
The U.S. is still assessing what the Russians were attempting to strike in Lviv in western Ukraine on Monday, according to Pentagon spokesman John Kirby.
Kirby said he would not describe Monday's airstrike as a "bombardment" and said he did not know Russia's intent.
"We don't have a clear sense of battle damage assessment about what they were targeting and what they hit. At this time, we don't have any indication that Western aid was targeted and/or hit or destroyed," Kirby said.
-ABC News' Luis Martinez
Apr 18, 2022, 3:23 PM EDT
US offering temporary protected status to Ukrainians in US as of April 11
The U.S. will offer temporary protected status to Ukrainians already in the country as of April 11, according to a new notice from the Department of Homeland Security in the Federal Register.
The Biden administration announced last month that it would offer Ukrainians this legal basis to stay in the U.S. if they had arrived before March 1. This new notice means that Ukrainians who have been in the U.S. as of April 11 can apply for the legal status, which will remain in effect for 18 months -- until Oct. 19, 2023.
U.S. Citizenship and Immigration Services estimates that about 59,000 Ukrainians could be eligible, according to the Federal Register notice.
Andriy Yermak, head of the Office of the President of Ukraine, has tweeted about the change, which he said was made at the Ukrainian government's request.
-ABC News' Conor Finnegan
Apr 18, 2022, 12:49 PM EDT
Thousands more Russian troops back in Ukraine
There are now 76 Russian battalion tactical groups -- each made up of about 800 to 1,000 troops -- inside Ukraine, all in the south or east of the country, a senior U.S. defense official said Monday. Last week there were 65 battalion tactical groups.
There are about 22 additional battalion tactical groups in the north of Ukraine, most likely refitting and resupplying after being depleted from earlier combat, the official said.
The besieged port city of Mariupol is still under threat of missile and artillery bombardment as Ukrainian forces continue to fight to push back Russian troops, according to the official.
Servicemen of Donetsk People's Republic militia walk past damaged apartment buildings near the Illich Iron & Steel Works Metallurgical Plant, in an area controlled by Russian-backed separatist forces in Mariupol, Ukraine, April 16, 2022. Mariupol, a strategic port on the Sea of Azov, has been besieged by Russian troops and forces from self-proclaimed separatist areas in eastern Ukraine for more than six weeks.
Alexei Alexandrov/AP
A woman walks along a street near an apartment building destroyed during Ukraine-Russia conflict in the southern port city of Mariupol, Ukraine, April 14, 2022.
Alexander Ermochenko/Reuters
Kyiv and Lviv are under long-range fire, the official said. Russian long-range bombers have hit both cities with air-launched cruise missiles over the last couple of days, the official said.
An Ukrainian interior ministry soldier collects unexploded shells, grenades and other devices in Hostomel, close to Kyiv, Ukraine, April 18, 2022.
Efrem Lukatsky/AP
"Our initial assessment is that they were going after primarily military targets, or what they believed to be military targets," the official said.
The U.S. is sending 18 howitzers -- short cannons used to fire projectiles -- to Ukraine and plans to begin training Ukrainians on the artillery in the coming days, the official said.
-ABC News' Matt Seyler
Apr 18, 2022, 12:08 PM EDT
269 civilians killed in Irpin: Police
Police say a total of 269 civilians have been killed in the Ukrainian city of Irpin, located near Kyiv and Bucha.
Ukrainian soldiers pass on a destroyed bridge at the entrance of Irpin, near Kyiv, on April 1, 2022, amid Russian invasion of Ukraine.
Ronaldo Schemidt/AFP via Getty Images
These fatalities are separate from the 410 bodies recovered in nearby Bucha last week.
