(Reuters) – Russia enters the third month in its incursion into Ukraine. Fighting that has claimed thousands of lives, uprooted millions of people and reduced many cities to rubble is not ending.

In spite of increasing sanctions and fierce Ukrainian resistance that was bolstered in part by Western arms and weapons, Russia continues its long-distance bombing and has launched an offensive to the east.

These are the key events of this year:

* Feb. 24: Russia invades Ukraine from three fronts in the biggest assault on a European state since World War Two. Tens to thousands flee.

* Russian President Vladimir Putin says he is launching a “special military operation” to demilitarise and “denazify” Ukraine. Volodymyr Zeleskiy, Ukraine’s President, tweeted: “Russia is on the path of evil. Ukraine is protecting itself.”

* Feb. 25: Ukrainian forces battle Russian invaders in the north, east and south. Authorities instruct residents in Kyiv to make Molotov cocktails for the defense of the capital.

* Feb. 26: A U.S. defence official says Ukraine’s forces are putting up “determined resistance”.

* Feb. 28: The first talks between the two sides make no breakthrough.

* March 1: Russia hits a TV tower in Kyiv and intensifies bombardment of Kharkiv in the northeast and other cities, in what is seen as a shift in tactics as Moscow’s hopes of a quick charge on the capital fade.

* A U.S. official says a miles-long Russian armoured column bearing down on Kyiv has not made any advances in the past 24 hours, bogged down by logistical problems.

* March 2: Russian forces bombard the southern port of Mariupol for 14 hours and stop civilians leaving, its mayor says – the start of Moscow’s blockade of the city. Russia denies targeting civilians.

* Russian troops reach the centre of the Black Sea port of Kherson and claim their first capture of a large urban centre.

* March 3: Russia and Ukraine agree to set up humanitarian corridors for fleeing civilians. One cargo ship sinks in the vicinity of a Ukrainian port after another one is hit with a blast at another.

* A million people have fled Ukraine, the U.N. refugee agency (UNHCR) says.

* March 4: Russian forces seize Zaporizhzhia nuclear power plant, Europe’s biggest. NATO denies Ukraine’s request for no fly zones and says it will escalate conflict. * March 6: “Rivers of blood and tears are flowing in Ukraine,” Pope Francis tells crowds in St. Peter’s Square. “This isn’t just a military operation. This is a war which sows misery, death and destruction.”

* March 8: Civilians flee the besieged city of Sumy in the first successful humanitarian corridor. According to the UNHCR, two million people have fled Ukraine. * March 9: Ukraine accuses Russia of bombing a maternity hospital in Mariupol, burying people in rubble. Russia claims that the hospital is no longer operational and has been taken over by Ukrainian fighters.

* March 13: Russia extends its war deep into western Ukraine, firing missiles at a base in Yavoriv close to the border with NATO member Poland. According to a local official, the attack has left 35 dead and 134 injured. * March 14: Russian journalist Marina Ovsyannikova bursts into a state TV studio during a live news bulletin, with a banner reading: “NO WAR. Stop fighting. Don’t believe propaganda. These people are lying.”

* March 16: Ukraine accuses Russia of bombing a theatre in Mariupol where hundreds of civilians are sheltering. Moscow denied it.

* March 25: Moscow signals it is scaling back its ambitions and will focus on territory claimed by Russian-backed separatists in the east, as Ukrainian forces go on the offensive to recapture towns outside Kyiv.

* March 29: Ukraine proposes adopting a neutral status during talks in Istanbul.

* March 30: More than 4 million people have fled Ukraine, the UNHCR says.

* April 1: Ukraine recaptures more territory around Kyiv from Russian soldiers who leave shattered villages and abandoned tanks as they move away from the capital.

* April 3/4: Ukraine accuses Russia of war crimes after a mass grave and bodies of people shot at close range are found in the recaptured town of Bucha. Kremlin claims that images of the bodies are staged and denies all responsibility.

* April 8: Ukraine and its allies blame Russia for a missile attack on a train station in Kramatorsk that killed at least 52 people trying to flee the looming eastern offensive. Russia denies responsibility.

* April 14: Russia’s lead warship in the Black Sea, the Moskva, sinks after an explosion and fire that Ukraine says was caused by a missile strike. Russia believes the ship was destroyed by an explosive ammunition blast. Washington claims that the ship was struck by two Ukrainian missiles. * April 18: Russia launches its assault on east Ukraine, unleashing thousands of troops in what Ukraine described as the Battle of the Donbas, a campaign to seize two provinces and salvage a battlefield victory. * April 20: More than 5 million people have fled Ukraine, the UNHCR says.

* April 21: Putin declares the southeastern port of Mariupol “liberated” after nearly two months of siege, despite leaving hundreds of defenders holding out inside a giant steel works.

* April 22: A Russian general says Moscow wants to take full control of southern and eastern Ukraine.