The unofficial spokesman of Russian protest band Pussy Riot is reportedly in a critical condition, with his family fearing he was poisoned.

Pyotr Verzilov, who invaded the football pitch during this year's World Cup final, was said to have been taken to hospital on Tuesday after he "began to lose his sight, speech and the ability to move around".

Fellow Pussy Riot member Veronika Nikulshina, who joined the activist on the pitch, told Russian website Meduza that he started to feel unwell shortly after a court hearing.

"When the paramedics arrived, he answered all their questions, saying, 'no, I didn't eat anything, no, I didn't take anything'," she said.

"He was getting worse even faster, and then he started convulsing. On the way [to the hospital], in the ambulance, he was already babbling... he fell into such a half-asleep, half-unconscious state that he stopped responding to me and didn't even recognise me anymore."


Image: Veronika Nikulshina said Verzilov's condition had deteriorated

She said Mr Verzilov's condition deteriorated later at the Bakhrushin City Clinical Hospital in Sokolniki and that he was moved to its toxicology wing.

Nikulshina claimed staff had refused to tell her if he had been poisoned and that doctors would only tell her that Mr Verzilov had started to "react to his name".

A tweet translated from the 30-year-old Russian activist's wife, Nadya Tolokno, read: "My brother Pyotr in resuscitation may have been poisoned. In the toxicological department in a very serious condition."

The claims come after Mr Verzilov was arrested along with Nikulshina, Olga Kurachyova and Olga Pakhtusova in July for their World Cup stunt, which saw them run onto the pitch wearing police uniforms.

Image: Verzilov has reportedly lost his ability to see, speak and move around

According to reports, Nikulshina and an unidentified friend were held by police after being stopped in Moscow.

Pussy Riot tweeted on Sunday: "Moscow police is now claiming that Nika and her friend were refusing to agree to a 'terrorist check' of their car - and they had to be arrested. Crazy accusations!"

It later added: "The girls have been arrested in their car for absolutely NOTHING. Moscow police is still mad after the World Cup action."

The punk rock band are vocal critics of Vladimir Putin and previously said their World Cup protest was intended to draw attention to human rights abuses in Russia.