Oleksandr Dubinsky, a parliament member who helped Rudy Giuliani four years ago in his unsuccessful efforts to find damaging information on Joe Biden for then-President Donald Trump, was put in jail by Ukrainian law enforcement officials on Tuesday.

Dubinsky is charged with treason for allegedly aiding Russia in its war against Ukraine. His arrest brings back attention to the attempts by Trump and his allies to gain political advantage by undermining Biden and his son Hunter Biden. Trump, who is facing legal troubles, is the leading Republican candidate to challenge Biden in next year’s election.

The Security Service of Ukraine, or SBU, and the State Bureau of Investigation told Dubinsky on Monday that he was under criminal investigation for state treason, according to statements posted on the Telegram messaging platform by the agencies.

The agencies said that Dubinsky, another ex-parliament member, Andriy Derkach, and former prosecutor Kostiantyn Kulyk were part of an organization run by Russia’s military intelligence agency, the GRU, which allegedly “did information sabotage to help the Russian Federation.”

The SBU statement said that the organization’s main goal was “to destabilize the social and political situation in Ukraine and discredit our state internationally.” It said that the offenders could face up to 15 years in prison and lose their property.

The three men were also sanctioned by the United States in 2020 and 2021 after they were accused of having ties to Russian intelligence services and trying to meddle in the 2020 U.S. presidential election.

On Tuesday morning, a court in Kyiv ruled that Dubinsky should be held for “at least 60 days” without bail, according to the State Bureau of Investigation.

The case did not mention Dubinsky by name and only referred to him as a “current people’s deputy.” But Dubinsky admitted the charges on his Telegram channel and claimed that he was not guilty.

He said in a video on Telegram after the court ruling: “I will be in jail until Jan. 12, 2024 – that’s what they call ‘New Year in a detention facility.’”