Russia’s bombing of a maternity hospital in Mariupol is “a war crime”, a UK defence minister says.

       James Heappey said Western countries would ensure that evidence is gathered to prove that the atrocity broke international law.

       “What Putin is doing is not a war waged between two militaries. Right now, he has besieged a number of Ukrainian cities and has waged a war against Ukrainian civilians,” the minister said.

       The attack – which sent photos worldwide of pregnant women being carried through the rubble on stretchers – underlined the increasingly desperate situation in the southern city.

       Russian troops have encircled it and cut off essential supplies, with more than 1,000 people killed by “continuous shelling” and 47 buried in a mass grave on Wednesday alone, Ukraine says.

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       People without water and have resorted to drinking snow, Ukraine says, while Russia shells evacuation routes, has mined roads out of the city and is firing on private cars trying to flee.

       Sergei Orlov, the deputy mayor of Mariupol, said he was “absolutely sure” that Russia knew the target of its bombing was a hospital.

       “This is the third hospital that they have destroyed in the city,” he told BBC Radio 4’s Today programme.

       “The previous day they destroyed hospital number nine by artillery shelling. This was a Covid hospital with 300 beds.

       “They have also attacked and destroyed a blood collection station in Mariupol. So, it is the third hospital, I’m absolutely sure they know what are their targets.”

       Mr Heappey also hit out at British troops going AWOL to fight in Ukraine, after the son of Conservative MP Helen Grant – former Royal Marine Ben Grant – arrived in the country.

       The armed forces minister said he knew of only three or four soldiers who had gone, but criticised going to “take some selfies, get some Instagram shots and then come home”.

       “They will be in an awful lot of trouble,” he told Sky News, after suggestions they will be prosecuted when they return to the UK.

       “It is illegal for British service personnel to first of all go absent without leave in the first place, but to go absent without leave in order to fight in a foreign war is simply unacceptable, and frankly risks the United Kingdom being wrongly claimed by Russia to be a belligerent in this.

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       “Service people who might think they are doing the right thing should reflect it is 100 per cent not the correct thing to be doing.”

       On the hospital attack, Mr Heappey added: “What matters beyond the outrage of the fact that this has happened in the first place is to make sure all this is catalogued so when, and they surely will be, President Putin and everybody in the military chain of command beneath him – because war crimes are committed at every level not just the ultimate decisionmaker – people will be held to account for what they are doing in. It’s utterly despicable.”