First major city falls as Russian attacks continue

March 3: It's been one week since Russia invaded its neighbour, Ukraine, and attacks are intensifying on key cities.

Russian forces have taken control of Kherson in the south - the first major city to fall.

Kherson is the first major city to be taken by Russia, after heavy fighting, since it invaded a week ago.

Its mayor, Igor Kolykhaev, said Russian troops had forced their way into the city council building and imposed a curfew on residents.

Several cities have come under intense shelling, with Wednesday one of the most destructive days of the fighting.

An investigation into possible war crimes and crimes against humanity committed in Ukraine has been launched by the International Criminal Court (ICC) in The Hague.

Russia has for the first time admitted taking heavy military casualties during its attack on Ukraine, with 498 troops killed and a further 1,597 injured. Ukraine says Russia's losses run into the thousands.

Ukraine reports that more than 2,000 civilians have died since the invasion began last Thursday. The conflict has also caused more than a million people to flee Ukraine, according to the UN.

In a Facebook post, Mr Kolykhaev said Russian forces were in control of Kherson, a port on Ukraine's southern Black Sea coast with a population of more than 280,000 people.

He urged Russian soldiers not to shoot at civilians, saying there were no Ukrainian forces in the city.

If they capture more southern cities, Ukrainian forces could be cut off from the sea.

In Mariupol, a strategic port near the Russian border, hundreds are feared killed by shelling.

Kyiv remains in government control and a large Russian armoured convoy remains some distance away.

More than one million people have already fled the country, the UN says.

Vladimir Putin's foreign minister warns a third world war would be nuclear but says Russians are not thinking about this.

Russian and Belarusian athletes are barred from the Winter Paralympics.