From the poisoning of former KGB agent Alexander Litvinenko to Yevgeny Prigozhin’s fiery plane crash, a number of high profile critics of Vladimir Putin have died, while others are in prison or exile. The Kremlin routinely denies involvement.
Jailed, shot dead in the street, fallen from windows or poisoned with tea spiked with polonium-210. Vladimir Putin’s opponents often find themselves suffering unfortunate fates.
The KGB spy-turned-president has been atop the Kremlin for two decades and has encountered a number of opponents and controversies.
Who are the people who have dared speak out against Mr Putin or defy the Kremlin, and where are they now?
Alexei Navalny
Born to factory owners in a village west of Moscow, Alexei Navalny grew to become perhaps the highest profile critic of Mr Putin’s time in power.
His political activisim, including extensive investigations into high-level corruption and running to be mayor of Moscow gained him fame and many believed he posed a threat to Mr Putin.
It was in August 2020 when his fight against the Russian president hit the global headlines.
He fell gravely ill on a flight from Siberia to Moscow and Navalny was flown, still in a coma, to Berlin.
His team accused the Kremlin of poisoning him, a charge the Kremlin denied.
German medics confirmed that he had been poisoned with novichok – a Soviet-era nerve agent – and his recovery took months.
Despite the danger, Mr Navalny elected to return to Russia where he was later arrested, convicted on charges he says are politically motivated, and remains in a Russian penal colony.
Boris Nadezhdin speaks during a meeting of the Russia's Central Election Commission in Moscow, Russia.
Boris Nadezhdin
Opposition politician Boris Nadezhdin declared that he would run against Putin in the 2024 presidential election.
Despite doubts that the 60-year-old could present a serious challenge to the incumbent leader, Mr Nadezhdin said he had gathered more than 200,000 signatures from across Russia.
He had surprised some analysts with his strong criticism of what the Kremlin calls its “special military operation” in Ukraine, calling the war a “fatal mistake” and vowing to try to end it through negotiations.
On 8 February, he said he had been barred from running in the election and the Central Election Commission said it had found flaws in signatures his campaign had collected.
He vowed to appeal to Russia’s supreme court, adding: “Taking part in the presidential election in 2024 is the most important political decision of my life. I am not giving up on my intentions.”
Speaking to Sky News last year, Mr Nadezhdin said he was not afraid of speaking out “because I have a long life” and he had faced death several times.