Russians have clashed with riot police in a rare, large protest after an activist was sentenced to four-years in a penal colony.

Fail Alsynov appeared in court on Wednesday accused of making a racist comment in a speech against plans to mine gold in the central Bashkortostan region using migrant workers.

Despite temperatures of -20C (-4F), thousands gathered outside the courtroom in Baymak demanding his freedom after the sentence was passed down.

Videos shared on social media showed a bus and three heavy police trucks, alongside crowds of protesters who squared up to officers who were holding shields and wearing helmets.

Demonstrators were seen throwing snowballs at police and shouting: “Freedom”, “Shame” and “We are with you”, while being tear-gassed. Some were shown washing their eyes and kneeling on the ground, while injured people were carried away.

The court found that on April 28 2023, the 37-year-old spoke at a rally in nearby Ishmurzino where he used the phrase “kara halyk”. It was translated as “black people” in Russian and considered an insult to people in the Caucasus and Central Asia.

Mr Alsynov says the speech was mistranslated and the actual meaning was akin to “common people”.

He told Rusnews: “What is happening in the Baymak court has nothing to do with rule nor with jurisprudence.”

Supporters said the charges were politically motivated.

Four people were reportedly detained and the local interior ministry said it had opened a criminal case into “mass rioting” – a crime that carries a maximum penalty of 15 years in prison.

Mr Alsynov was previously head of a group called Bashkort, that promoted the Bashkir language and culture. It was dissolved in 2020 after being categorised by the government as an extremist organisation.

Last year he was fined for criticising Moscow’s offensive in Ukraine online, saying it was not in Bashkortostan’s interests.

According to local media, Mr Alsynov called Russia’s mobilisation drive a “genocide of the Bashkir people” and said the offensive “was not our war”.