The half-million city of Mariupol was a significant industrial city before the Russian invasion and employed about 100,000 port workers.

Now the strategic location next to the Sea of ​​Azov has made the city one of the most important targets of the war.

The reason is that Putin wants to use the city to link the strip of land between the Russian border and the annexed Crimea.

- If you take Mariupol, you control the entire part of the south coast and can freely link the breakaway republics with the Russian Federation, says Joakim Paasikivi, lieutenant colonel and teacher of war strategy at the Swedish National Defense College.

Attacks on children's hospitals

According to local authorities, 2,300 people have been killed in the attacks on the city so far, several of which have ended up in mass graves.

Russia has, among other things, been accused of attacks on a local art school on Sunday and of bombing a children's hospital on March 9.

The attacks are denied by Russian authorities.

Hundreds of thousands of civilians are still trapped in the city - without access to electricity, gas or water.

- It shows above all the indifference of the Russian forces.

They have no qualms and use the hardships of civilians as a means of pressure.

The purpose is to minimize the city to gravel and then it does not matter if it is the elderly or children who stand in the way, says Joakim Paasikivi.

"Balanced on a knife edge"

This is not the first time Mariupol has been threatened by Russian interests.

In the summer of 2014, the same year as the annexation of Crimea, the city was controlled by Russian separatist forces for a few months before being taken back by the Ukrainian military.

- It is a city that has long been balanced on a knife edge.

At the same time, no one could have imagined that the war would come with this force, says Fredrik Wadström, Swedish Radio for this Moscow correspondent in SVT's Morgonstudion.

Paasikivi: "May fall in a few days"

The capture of Mariupol will not be decisive for the entire war but can give the Russian troops new opportunities to mobilize to the west, says Joakim Paasikivi.

He fears it could go fast.

- Several signs indicate that Russia will succeed in grinding down the resistance.

The Ukrainian troops have fought bravely but they are at a disadvantage and are surrounded.

I fear that Mariupol will fall within a few days.