The Foreign Office has announced sanctions against the "despicable" individuals linked to atrocities carried out by the Wagner mercenary group across Africa.
Foreign Office Minister Andrew Mitchell said the Russian mercenary unit, as well as assisting the Kremlin with its invasion of Ukraine, was "acting with impunity" in countries such as Mali, Central African Republic (CAR) and Sudan.
Among the 13 individuals and businesses sanctioned is Konstantin Aleksandrovitch Pikalov, the so-called 'right-hand man' of the group's head Yevgeny Prigozhin.
The UK government said he had been responsible for the torture and targeted killings of civilians.
Wagner leader Mr Prigozhin, who led a mutiny against Moscow last month, has already been sanctioned by Britain, along with several of his key commanders, for their part in Russia's invasion of Ukraine.
Andrew Mitchell, minister for development and Africa, said: "The Wagner Group is committing atrocities in Ukraine, as well as acting with impunity in countries like Mali, Central African Republic and Sudan.
"Wherever Wagner operates, it has a catastrophic effect on communities, worsens existing conflicts and damages the reputations of countries that host them.
"These sanctions expose despicable individuals who have commissioned violations of international humanitarian law, holding them to account for the severe harm they are inflicting on innocent civilians for financial gain."
Sanctions are imposed by the Foreign Office in a bid to limit the "financial freedom" of those targeted, by preventing UK citizens, companies and banks from dealing with them.
Another of those listed was the head of the Wagner Group in Mali, Ivan Aleksandrovitch Maslov.
According to the Foreign Office, Wagner mercenaries, alongside Malian forces, massacred at least 500 people in Moura in March 2022, including carrying out summary executions, rape and torture.
The Wagner sanctions come a week after the UK imposed punishments and restrictions on businesses linked to the leaders on both sides in the Sudanese conflict.
The measures applied to three businesses associated with the Sudanese Armed Forces and three linked to its rival in the power struggle, the Rapid Support Forces.
Britain has accused the Wagner Group of providing weapons and military equipment to fighters in Sudan.
It said three businesses acting as fronts for Mr Prigozhin's unit had been included in Thursday's sanctions package, citing the continued risk the firms - including M-Invest and its subsidiary Meroe Gold - pose to peace and stability in the country.
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