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.
May 08, 2022, 3:11 PM EDT
U2's Bono, The Edge perform surprise concert in Kyiv
U2's frontman Bono and lead-guitarist The Edge surprised fans in Kyiv on Sunday by performing an impromptu concert in the Ukrainian capital's central metro station.
The two Irish rockers delivered a nearly hour-long set at the Khreshchatyk Metro Station, Kyiv's busiest metro station, as several dozen fans watched.
U2 rock band frontman Bono sings during a performance for Ukrainian people inside a subway station in Kyiv, Ukraine May 8, 2022.
Valentyn Ogirenko/Reuters
"The people of Ukraine are not just fighting for your own freedom, you're fighting for all of us who love freedom," Bono told the crowd between songs.
Bono, The Edge and Ukrainian serviceman, frontman of the Antytila band Taras Topolia sing during a performance for Ukrainian people inside a subway station in Kyiv, Ukraine May 8, 2022.
Valentyn Ogirenko/Reuters
The musicians were joined on one of the station's platforms by Taras Topolia, frontman of Ukrainian pop rock band Antytila. Topolia presented Bono with a piece of shrapnel he said was the remains of a missile that struck near the base in Kyiv where he is currently serving in the Ukrainian Army.
May 09, 2022, 8:41 AM EDT
US and G-7 allies announce new sanctions against Russia
The United States and its G-7 allies announced a new round of sanctions on Sunday against Russia, including some aimed at crippling three of Russia's largest state-controlled television stations.
The new sanctions were announced after leaders from the G-7 group held a virtual summit with Ukrainian President Volodymyr Zelenskyy.
"Putin has failed in his initial military objective to dominate Ukraine -- but he has succeeded in making Russia a global pariah. Today, the United States, the European Union and G7 committed to ratchet up these costs by collectively taking further measures, consistent with each partner’s respective legal authorities and processes,” reads a fact sheet of the new measures released by the White House.
Smoke rises from an explosion at a plant of Azovstal Iron and Steel Works during Ukraine-Russia conflict in the southern port city of Mariupol, Ukraine May 8, 2022.
Alexander Ermochenko/Reuters
Sanctions will be imposed against Russia's Channel One, Russia-1 and the NTV Broadcasting Company, including cutting off the outlets' access to technology like video cameras, microphones, lighting equipment and software services, according to the fact sheet. Advertising dollars derived from the United States will also be prohibited from funding the companies.
“Russia can try to produce these components domestically but the idea here is to make that commercially difficult, unprofitable, put more of the burden on the Russian state. We’re not going to be in the business of helping them broadcast the lies and deceit that you hear from Putin every day,” a senior Biden administration official said.
The entire G-7 also announced it is committed to phasing out or banning the import of Russian oil.
Additionally, the new sanctions prohibit anyone from the United States from providing accounting, trust, corporate formation and management consulting services to members of Russian Federation.
The United States is also imposing about 2,600 visa restrictions for Russian and Belarussian officials, and creating a new visa restriction policy for Russian Federation military officials and “Russia-backed” or “Russia-installed” officials believed to be involved in human rights abuses, violations of international humanitarian law or corruption in Ukraine.
New restrictions are to be imposed on wood products, industrial engines, motors, and bulldozers, according to Biden administration officials.
The administration is also sanctioning Promtekhnologiya LLC, a Russian company that manufactures rifles and weapons Russian forces have used in Ukraine.
In addition to the new sanctions, the U.S. Nuclear Regulatory Commission is suspending licenses for exports of special nuclear material, byproduct material and deuterium, or heavy hydrogen, to Russia.
ABC News' Armando Garcia
May 08, 2022, 10:52 AM EDT
Jill Biden, in Europe, makes surprise visit to Ukraine
First lady Jill Biden, in Eastern Europe to show American support for its NATO allies, made a surprise visit to Ukraine Sunday, where she met with that nation's first lady.
Biden's motorcade crossed into Ukraine from Slovakia, where earlier in the day she toured refugee aid stations.
In Ukraine, she visited a public school in the city of Uzhhorod, where she met privately with the first lady of Ukraine, Olena Zelenska, for about half an hour.
U.S. first lady Jill Biden receives flowers from Olena Zelenska, wife of Ukraine's President Volodymyr Zelenskiy, outside a public school in Uzhhorod, Ukraine, May 8, 2022.
Susan Walsh/Pool via Reuters
"I thought it was important to show the Ukrainian people that this war has to stop," Biden told reporters following the visit. "And this war has been brutal. And that the people of the United States stand with the people of Ukraine."
"We understand what it takes for the U.S. first lady to come here during a war where the military actions are taking place every day, where the air raid sirens are happening every day, even today," Zelenska said through a translator. "We all feel your support. We all feel the leadership of the U.S. president."
"We would like to note that Mother’s Day is a very symbolic day for us," Zelenska added. "Because we also feel your love and support during such an important day."
-ABC News' Armando Garcia
May 08, 2022, 6:10 AM EDT
Dozens missing after Russian strike on Ukrainian school shelter, official says
Emergency responders were searching on Sunday for dozens of missing civilians after Russian forces struck a school building being used as a shelter in Bilohorivka, a village in eastern Ukraine, a local official said.
About 90 civilians had taken shelter in the building before it was destroyed on Saturday, Serhiy Haidai, regional governor of Luhansk in eastern Ukraine, said.
Emergency crew stands around near burning debris, after a school building was hit as a result of shelling, in the village of Bilohorivka, Luhansk, Ukraine, May 7, 2022.
State Emergency Services via Reuters
Emergency crew tend to a fire near a burning debris, after a school building was hit as a result of shelling, in the village of Bilohorivka, Luhansk, Ukraine, May 8, 2022.
State Emergency Services/via Reuters
About 30 people had been rescued and two bodies were found in the rubble, the local emergency services said. Rescue efforts resumed at dawn on Sunday, Haidai said on social media.