Russian opposition leader Alexey Navalny is facing an even longer stint in jail after being sentenced to 19 years in prison on extremism charges, Russian media report, a fresh blow to a fierce critic of Russia’s President Putin that comes amid an intensifying crackdown on dissent.

Navalny was accused of creating an extremist community, financing extremist activities and a number of other crimes.

He was found guilty on Friday at the high-security penal colony in which he has been detained.

Navalny is already serving sentences totaling 11-and-a-half years in a maximum security facility on fraud and other charges that he says were trumped up.

He and his supporters claim that his arrest and imprisonment were politically motivated, intended to silence his criticism of Putin.

The trial ended in June and took place behind closed doors at the IK-6 penal colony at Melekhovo, around 155 miles east of Moscow, where Navalny is being held.

Friday’s verdict extends Navalny’s time in prison and raise further concerns about the brutal crackdown on Putin’s opponents that has been accelerated since Moscow’s invasion of Ukraine.

The European Union was quick to condemn the sentence, saying it reiterated its “deep concern about reports of repeated ill-treatment, unjustified and unlawful disciplinary measures, and harassment amounting to physical and psychological torture by prison authorities against Mr Navalny.”

Navalny has been incarcerated in Russia since his return to the country in January 2021, on charges of violating terms of probation related to a years-old fraud case, which he dismisses as politically motivated.

There have been concerns about his wellbeing: Navalny lost weight and suffered stomach pain earlier this year, leading to fears among his lawyers that he had again been poisoned.

He had previously been taken from Russia to Germany in August 2020, after he was poisoned with the Soviet-era nerve agent Novichok. Navalny arrived comatose at a hospital in Berlin, following a medical evacuation flight from the Siberian city of Omsk.

A joint investigation by CNN and the group Bellingcat implicated the Russian Security Service (FSB) in Navalny’s poisoning, piecing together how an elite unit at the agency had followed Navalny’s team throughout a trip to Siberia, when he fell ill.

The investigation also found that this unit, which included chemical weapons experts, had followed Navalny on more than 30 trips to and from Moscow since 2017.

Russia denies involvement in Navalny’s poisoning. Putin himself said in December 2020 that if Russian security services had wanted to kill Navalny, they “would have finished” the job.

Although the Russian authorities’ targeting of Navalny pre-dates Moscow’s invasion of Ukraine, the country has cracked down even more dramatically on internal opposition and free speech since launching the war.

An expanded and intentionally vague law on “foreign agents” came into effect late last year, requiring organizations and individuals engaging in political activity and receiving funding from abroad to adhere to draconian rules and restrictions.

Russia has also restricted access to Facebook, many Western news sites, and independent media in the country. Peaceful protests were quickly shut down and thousands arrested after Moscow’s invasion.

And the government has adopted a law criminalizing the dissemination of what it called “deliberately false” information about the Russian armed forces, with a maximum penalty is 15 years in prison.

Navalny has nonetheless been a vocal critic of the conflict. On the anniversary of the invasion in February, he called it “an unjust war of aggression against Ukraine under ridiculous pretexts.”