Russian forces attacked Ukraine early Thursday morning, launching an offensive that threatens to kill thousands of people, force millions more to flee, and wreak havoc on Europe.

The Ukrainian interior ministry told CNN that there were missile strikes from the capital to the eastern city of Kharkiv.

US President Joe Biden said in a statement that the world was praying for the people of Ukraine, who were being attacked by Russian military forces.

There was a formal request for military intervention from Russian-backed rebels in eastern Ukraine before the invasion.

On the eve of the attack, Ukrainian President Volodymyr Zelensky took to the airwaves in a last-ditch appeal for peace, while promising that Ukrainians would fight back against any Russian incursion.

Hours later, in an early morning address, Russian President Vladimir Putin effectively declared war, saying that Russian forces would strive for de-Nazification of Ukraine. CNN reported that there were blasts in the port city of Odessa and in the cities of Kharkiv and Kyiv.

The attack will be a full scale and comprehensive military assault. Air strikes, amphibious landings, cyber attacks, and a large ground force would be included in the invasion, according to the Florida Republican.

The landing operation was taking place on the Azov sea.

Russia amassed troops, tanks, and amphibious ships near the borders of Ukraine. By the time of the attack, Russia had amassed tens of thousands of troops on the borders of Ukraine.

The US and NATO didn't believe Russia's claims that it was withdrawing troops from the borders of Ukraine.

President Biden warned last week that Russian forces will besiege the capitol of Ukraine, which has a population of nearly 3 million people. He unveiled a new round of sanctions against Russian officials in response to the deployment of troops to the eastern Donbas region, which he characterized as the beginning of a Russian invasion of Ukraine.