Armed men, thought to be Russians, seize a Ukrainian military base in the Crimean port city of Sevastopol. Meanwhile, Ukraine's premier rejects Crimea's planned referendum.
Here at Channel 4 News we try hard to keep the plight of people in the Central Africa Republic on the radar - and Monday's UN report makes for sobering reading.
The escalating crisis in Crimea has set a number of western powers against Russia in a battle of words that includes threats of "costs" and allegations of illegal behaviour.
Putin is no salesman for democracy - but for now "big bad Russia", "big nasty Putin" and "poor heroic Ukraine" look a little too simplistic to me.
Russia's defence ministry dismisses claims that it had threatened Ukrainian troops in Crimea with a "real assault" if they did not surrender by the early hours of Tuesday morning as "utter nonsense".
Prime Minister David Cameron says it would be wrong for British ministers to attend the Paralympics in Sochi because of the serious situation in Ukraine.
Members of Ukraine's new government are brought out to face the people at Kiev's independence square. In Russia, President Vladimir Putin puts troops on alert.