What's happened in the 100 days since Russia invaded Ukraine

Russia's invasion of Ukraine entered its100th day on Friday with no end in sight to the fighting thathas killed thousands, uprooted millions and reduced cities torubble.

After abandoning its assault on the capital, Kyiv, Russia is pressing on in the east and south in the face of mounting sanctions and a fierce Ukrainian counter-offensive bolstered by Western arms.

Some key events in the conflict so far:

Feb. 24

Russia invades Ukraine from three fronts in thebiggest assault on a European state since World War Two. Tens ofthousands flee.Russian President Vladimir Putin announces a "specialmilitary operation" to demilitarize and "de-Nazify" Ukraine.Ukrainian President Volodymyr Zelensky tweets: "Russia has embarked on a path of evil, but Ukraine is defending itself."

Feb. 25:

Ukrainian forces battle Russian invaders in thenorth, east and south. Artillery pounds Kyiv and its suburbs.

March 1

A U.S. official says a miles-long Russian armouredcolumn bearing down on Kyiv is beset by logistical problems.Russia hits a TV tower in Kyiv and intensifies its long-rangebombardment of Kharkiv in the northeast and other cities, inwhat is seen as a shift in Moscow's tactics as its hopes of aquick charge on the capital fade.

March 2

Russian forces start a siege of the southeasternport of Mariupol, seen as vital to Moscow's attempts to link theeastern Donbas region with Crimea, the Black Sea peninsulaRussia seized in 2014.Russian troops enter the Black Sea port of Kherson, the firstlarge urban centre captured.One million people have fled Ukraine, according to the UN High Commissioner for Refugees (UNHCR).

March 4

Russian forces seize Zaporizhzhia nuclear power plant, Europe's biggest. NATO rejects Ukraine's appeal forno-fly zones, saying they would escalate the conflict.

March 8

Civilians flee the northeastern city of Sumythrough the first successful humanitarian corridor. Two million havenow fled Ukraine, the UNHCR says.

March 9

Ukraine accuses Russia of bombing a maternityhospital in Mariupol, burying people in the rubble. Russia saysUkrainian fighters were occupying the building.

March 13

Russia extends its war deep into western Ukraine,firing missiles at a base near the border with NATO memberPoland.

March 16

Ukraine accuses Russia of bombing a Mariupoltheatrewhere hundreds of civilians are sheltering. Moscowdenies it.

March 25

Moscow signals a shift in focus to making gains inthe east, while Ukrainian forces press to recapture townsoutside Kyiv.

March 30

More than fourmillion people have fled Ukraine, theUNHCR says.

April 3, 4

Ukraine accuses Russia of war crimes after a massgrave and bodies of people shot at close range are found in therecaptured town of Bucha. The Kremlin denies responsibility andsays images of bodies were staged.

April 8

Ukraine blames Russia for a missile attack on atrain station in Kramatorsk that killed at least 52 peopletrying to flee the looming eastern offensive. Moscow deniesresponsibility.

April 14

Russia's lead warship in the Black Sea, the Moskva,sinks after what Ukraine says was a missile strike. Russiablames an ammunition explosion.

April 18

Russia launches what Ukraine describes as theBattle of Donbas, a campaign to seize two provinces and salvagea battlefield victory.

April 21

Putin declares Mariupol "liberated" after nearlytwo months of siege, but hundreds hold out insidethe city's huge Azovstal steelworks.

April 25, 26

Moldova's pro-Russian breakaway region ofTransdniestria says blasts hit a ministry and two radio masts.It blames neighbouring Ukraine. Kyiv accuses Moscow of stagingthe attacks to try to widen the conflict.

April 28

Russia fires two missiles into Kyiv during a visitby UNSecretary-General Antonio Guterres, Ukraine says. TheKremlin accuses Ukraine of attacking Russian regions near the border.

May 1

About 100 Ukrainian civilians are evacuated fromMariupol's ruined Azovstal steelworks, in what the UnitedNations says is a "safe passage operation."

May 7

As many as 60 people are feared dead after a bombstrikes a village school in Bilohorivka, inEastern Ukraine, theregional governor says.

May 9

Putin exhorts Russians to battle in a defiant VictoryDay speech, but is silent about plans for any escalation inUkraine.

May 10

Ukraine says its forces have recaptured villagesnorth and northeast of Kharkiv in a counter-offensive.

May 12

More than sixmillion people have fled Ukraine, theUNHCR says.

May 14

Ukrainian forces have launched a counteroffensivenear the eastern Russian-held town of Izyum, the governor says.

May 18

Finland and Sweden apply to join NATO, a move thatwould lead to the expansion of the Western military alliancethat Putin aimed to prevent.

May 20

Russia says the last of Ukrainian fighters holdingout at Mariupol's Azovstal steelworks have surrendered. Hoursearlier, Zelensky said Ukraine's military had told those inside they could get out and save their lives.

May 21/22

Russia launches an offensive in Luhansk, one oftwo provinces in Donbas, focusing the attack on twin cities ofSloviansk and Severodonetsk.

May 23

In the first war crimes trial of the conflict, a Kyivcourt sentences a young Russian tank commander to life in prisonfor killing an unarmed civilian.

May 25

Putin signs a decree simplifying the process forresidents of newly captured districts to acquire Russiancitizenship and passports in a bid to solidify Moscow's grip onthe seized territory.

May 29

Russia's Foreign Minister Sergei Lavrov calls the"liberation"of Donbas an "unconditional priority" for Moscow,while Russian forces appear close to seizing the entire Luhanskregion there after days of slow but steady gains.

May 31

Local officials say it is no longer possible toevacuate civilians trapped in Severodonetsk, where Ukrainianforces are still holding out but much of the city is underRussian control.

June 1

Russia criticizes U.S. decision to supply advancedrocket systems to Ukraine, warning it could widen the conflictand increase the risk of direct confrontation with Washington.

June 2

Zelensky pleads for more Western arms to helpUkraine reach an "inflection point" and prevail in the war. The European Union gives final approval to new sanctions on Russianoil and top bank Sberbank.

June 3

Ukraine does not plan to use multiple-launch rocketsystems it receives from the United States to attack facilitiesin Russia, a Ukrainian presidential adviser says. Britain's Defence Ministry said that on the 100th day of Russia's invasionMoscow has failed to achieve its initial objectives to seizeKyiv and centres of government but is achieving tactical successin the Donbas.