Russia invades Ukraine on many fronts in 'brutal act of war'

Russia launched a full-scale invasion of Ukraine on Thursday, unleashing airstrikes on cities and military bases and sending in troops and tanks from three sides in an attack that could rewrite the global post-Cold War security order. Ukraine's government pleaded for help as civilians piled into trains and cars to flee.

Scores of Ukrainians, civilians and service members alike, were killed in the first full day of fighting.

Russian President Vladimir Putin ignored global condemnation and cascading new sanctions as he unleashed the largest ground war in Europe since World War II and chillingly referred to his country's nuclear arsenal. He threatened any country trying to interfere with "consequences you have never seen," as a once-hoped for diplomatic resolution now appeared impossible.

Ukrainian forces braced for more attacks after enduring a Russian barrage of land- and sea-based missiles, an attack that one senior U.S. defence official described as the first salvo in a likely multi-phase invasion aimed at seizing key population centers, "decapitating" Ukraine's government and installing a new one. Already, Ukraine officials said they had lost control of the decommissioned Chernobyl nuclear power plant, scene of the world's worst nuclear disaster.

"Russia has embarked on a path of evil, but Ukraine is defending itself and won't give up its freedom," Ukrainian President Volodymyr Zelensky tweeted. His grasp on power increasingly tenuous, he pleaded Thursday for even more severe sanctions than the ones imposed by Western allies and ordered a full military mobilization that would last 90 days.