By The Visual Journalism Team BBC News
Air raid sirens are sounding again in Ukraine’s capital Kyiv, at the end of the fifth day of the Russian invasion.
The Russians launched their attack last Thursday from three main directions: north, south and east.
Dozens of targets have been struck, as Russian troops have poured into Ukraine.
Russian forces arrived near Obolon on the outskirts of Kyiv on Friday, but so far have not advanced into the centre of the capital.
The Ukrainian military says Russian troops have repeatedly tried to storm the outskirts of the capital without success.
On Monday satellite images revealed a long convoy of Russian military vehicles heading south towards Kyiv.
Hostomel airport, to the west of the capital, has been the scene of fierce fighting and has changed hands multiple times in the past few days, according to the Institute for the Study of War.
On Monday it was held by Ukrainian forces.
Russian airborne and special forces troops were reported to be involved in urban clashes in north-western Kyiv, but mechanised forces such as tanks and armoured vehicles are not yet in the capital.
On Sunday, there were reports of clashes with so-called saboteur groups on the city streets – and an oil depot was hit at Vasylkiv south of the city.
A residential block in the suburb of Bucha was hit by shelling, and there was heavy fighting in nearby Irpin.
Russia is now in full control of significant parts of Ukraine’s territory.
After Ukraine’s air defences and other military infrastructure came under attack on Thursday, columns of tanks moved into position, backed up by artillery and air power.
Troops have spread across parts of the north, east and south, with missile strikes and artillery clearing the way for advancing Russian forces.
Some analysts say overall progress by Russian troops has been slower than expected. But after the apparent pause in major operations over the weekend, the Russians could resume the offensive using greater air power and artillery support.
From the north, Russian troops crossed the border into Ukraine at the three-way junction between Ukraine, Russia and Belarus, at Senkivka.
In recent weeks, a huge deployment of Russian troops gathered close to Novye Yurkovichi and Troebortno, including “the entire 41st army”, according to Michael Kofman of the US-based Center for Naval Analyses.
The British Ministry of Defence says the bulk of Russia’s ground forces remain more than 30km (18.6 miles) from Kyiv, their advance slowed by Ukrainian forces defending Hostomel airport.
Armoured columns, including tanks and multiple launch rocket systems, have moved towards Chernihiv, where they have faced strong Ukrainian opposition. The city faced heavy shelling from Russian troops overnight, but remains in Ukrainian hands.
A second, more rapid advance has come down the west side of the Dnieper river via Chernobyl, taking control of a large area to the north and west of Kyiv.
On Monday dozens of people were killed in Russian missile strikes on Ukraine’s second city, Kharkiv, Ukrainian officials reported.
The day before Russian forces breached Kharkiv and and images emerged showing Ukrainian troops firing rocket propelled grenades on street corners and Russian troops, on foot, moving behind armoured vehicles.
Later in the day, Ukrainian officials said the Russian attack had been repelled.
Reports say shelling has continued around Donetsk, which has come under attack from troops crossing from Belgorod in western Russia.
There are thought to be about 15,000 Russian-backed separatists in Donetsk and Luhansk, who may help a Russian advance. Ukraine believes the figure is higher.
Fighting has also continued around Sumy.
Russian forces have made a rapid advance from Crimea, moving north-east and north-west.
To the north-east, there has been heavy fighting around Mariupol, a major port.
On Sunday, Russian forces pushed slowly towards Zaporizhzhia and east along the Sea of Azov coast towards Mariupol. The port city of Berdyansk is said to have fallen to Russian troops.
An advance from Mariupol to the east would create a land bridge between Crimea and territory held by pro-Russian separatists in Donetsk and Luhansk.
The Russian defence ministry claims its troops entered Melitopol without resistance – although western officials suggested it is still in Ukrainian hands.
Ukrainian forces have held the city of Kherson after heavy fighting and say they have thwarted an attempted amphibious landing by Russian troops in Odesa.
In the days leading up to the invasion, Russia positioned landing ships capable of deploying main battle tanks, armoured vehicles and personnel, off the Ukrainian coast in a major build-up in the Black Sea and the Sea of Azov.
Graphics by Zoe Bartholomew, Mark Bryson and Sana Dionysiou