The UK government is set to put the Russian mercenary group, Wagner, on its list of terrorist organisations.
Wagner's future is very uncertain, after the death of its founder, Yevgeny Prigozhin, in a plane crash in western Russia in August.
What is the Wagner group and how big is it?
Yevgeny Prigozhin said he founded Wagner in 2014.
Although mercenary forces are technically illegal in Russia, Wagner registered as a "private military company" in 2022.
Prigozhin was a wealthy businessman and convicted criminal, known as "Putin's chef" because he provided catering for the Kremlin.
Wagner's first field commander was Dmitry Utkin, a former Russian special forces officer. The group was named after his radio call sign.
Most Wagner mercenaries initially came from Russia's special forces and other elite units, and in its early days the group was thought to number about 5,000.
The group has also operated in Syria, Mali, the Central African Republic, Sudan and Libya.
What is the UK doing about Wagner?
Home Secretary Suella Braverman is asking Parliament to pass a draft order allowing Wagner's assets to be treated as terrorist property and seized.
The order would also make it illegal to be a member of Wagner, or to support it.
Ms Braverman said Wagner fighters "are terrorists, plain and simple," and a "threat to global security".
In response, the Kremlin said that the group does not exist from a legal point of view.
In January 2023, the US designated Wagner a "Transnational Criminal Organization".
A number of Members of the European Parliament (MEPs) have called on the EU to add the group to its terrorist list.
What crimes have Wagner fighters been accused of?
Ukrainian prosecutors say three Wagner mercenaries killed and tortured civilians near Kyiv in April 2022, alongside regular Russian troops.
German intelligence says Wagner troops may also have massacred civilians in Bucha in March 2022.
In July 2023, the UK sanctioned Wagner's businesses in Africa, accusing it of "executions and torture in Mali and the Central African Republic and threats to peace and security in Sudan".
The US military previously accused Wagner mercenaries of planting landmines in and around the Libyan capital, Tripoli.
What did Wagner do for Russia in Ukraine?
Wagner troops were heavily involved in the battle for Bakhmut, in eastern Ukraine, which they captured for Russia in May 2023.
During the fighting, Prigozhin repeatedly criticised Russia's army chief, Valery Gerasimov, and defence minister, Sergei Shoigu, for under-supplying Wagner's troops, many of whom were killed or injured.
In June 2023, some 5,000 Wagner fighters staged a mutiny. They occupied the southern Russian city of Rostov-on-Don, and marched on Moscow, with the stated aim of ousting Gerasimov and Shoigu.
Prigozhin halted the advance after making a deal with Russian President Putin, which was brokered by the Belarusian leader Alexander Lukashenko.
Putin said Wagner's fighters could either join the Russian army or go to Belarus with Prigozhin.
In July, a US military spokesman said Wagner troops were no longer thought to be "taking part in hostilities" in Ukraine.
What has Wagner been doing in Belarus?
The Polish government is reported to have said there are between 3,500 and 5,000 Wagner mercenaries in Belarus.
They are thought to be based at military camps in the south of the country, at Tsel and Brestsky.
The Belarusian defence ministry says they are training the country's territorial forces.
What has Wagner been doing in Africa?
In a speech to Wagner mercenaries in Belarus in July, Prigozhin said the group would expand its operations in Africa.
An estimated 1,000 Wagner fighters have been in Mali, in western Africa, since December 2021.
They were hired to combat armed Islamist groups, replacing the UN and French peacekeeping forces which had previously operated there.
There are an estimated 1,000 Wagner fighters in the Central African Republic (CAR), who the UK says operate behind a front organisation called the Officers Union for International Security.
That group's leader has said it is training soldiers in CAR to fight rebel forces, and helping to protect supply lines to cities.
In Libya, Wagner troops are supporting the forces of General Khalifa Haftar.
Wagner's mercenaries have also been in Syria since 2015, supporting pro-government forces and guarding oilfields.
What do we know about the plane crash which killed Prigozhin?
Russian officials said Yevgeny Prigozhin and nine other passengers died when a private plane flying between Moscow and St Petersburg crashed north of the capital on 23 August.
Senior Wagner fighter Dmitry Utkin was also on board.
UK defence sources told the BBC that Russia's FSB intelligence agency was thought likely to have been responsible.