Prime Minister Justin Trudeau says Canadian consular officials are attempting to provide support to a dual citizen who is in hospital in Russia amid reports of a possible poisoning.

The online news site Meduza reports that Pyotr Verzilov from the punk band Pussy Riot was rushed to hospital in Moscow on Tuesday evening.

Bandmate Veronika Nikulshina told the site that Verzilov laid down to rest after a court hearing on Tuesday and woke up with loss of vision, speech problems and mobility issues.

“He was getting worse even faster, and then he started convulsing,” she told Meduza. “On the way (to the hospital), in the ambulance, he was already babbling,” she added. “He fell into such a half-asleep, half-unconscious state that he stopped responding to me and didn’t even recognize me anymore.”

Prime Minister Justin Trudeau told reporters in Saskatoon on Thursday that consular officials have reached out to the hospital.

“It is of concern obviously, particularly given actions of recent months by the Russians in the U.K., so we are certainly taking this very seriously and working with the individual,” Trudeau said.

“It is too early to draw any conclusions about what has happened or how it has happened,” Trudeau added. “We just know that there’s a Canadian who is in the hospital that we need to make sure we’re getting support to.”

Bill Browder, a financier on a campaign to expose killings by the Russian regime, told CTV Question Period Host Evan Solomon on Thursday that he has met Verzilov through his advocacy.

“These are really brave people because they’re actually challenging Putin inside of Russia,” he told Solomon while speaking on CFRA radio. “That is a very dangerous thing to do. It looks like from what we know so far that Putin has decided to retaliate.”

“There’s no question that the Russian government, the Putin regime, to get rid of their enemies, poisons them, shoots them—kills them,” Browder added.

The reports come just as two Russians accused by the United Kingdom of poisoning a former Russian spy and his daughter went on Russian television and claimed they were only vacationing in England at the time of the poisoning.

Alexander Petrov and Ruslan Boshirov told RT that they went for a weekend trip to Salisbury to see its famous cathedral. The United Kingdom, meanwhile, says they were spies sent to kill double-agent Sergei Skripal with the nerve agent Novichok.

Pussy Riot have long protested against the government of Vladimir Putin, most recently at the FIFA World Cup final in July. Nikulshina and Verzilov both served 15-day sentences as a result of their interruption. Verzilov is the band’s producer, according to Meduza.

With files from The Associated Press