Authorities in Ukraine on Tuesday opened an investigation into a former government prosecutor who is indirectly connected to allegations that have prompted Democratic lawmakers in the U.S. to launch an impeachment inquiry into President Donald Trump.

Ukraine's State Bureau of Investigations (SBI) opened criminal proceedings against Yuriy Lutsenko over his possible abuse of power, the government agency said.

It said that Lutsenko and other former lawmakers may have conspired to "provide cover" for illegal gambling businesses in Ukraine. Lutsenko disputes the allegations.

The claims were first raised by David Arakhamia, a member of Ukraine President Volodymyr Zelensky's Servant of the People party. In a Facebook post, Lutsenko said Arakhamia and state investigators "must have a great imagination to accuse me of this."

Lutsenko was fired as Ukraine's top legal official last month.

The allegations unveiled Tuesday are not directly related to the U.S. impeachment inquiry, which stems from a summer call Trump had with Zelensky. In the call, Trump asked for help investigating political rival Joe Biden, according to a White House-released summary of the call and a whistleblower complaint.

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Lutsenko has drawn scrutiny in recent days because he was Ukraine's prosecutor general – broadly equivalent to the attorney general in the United States – when an investigation was halted into Burisma, a Ukrainian company. At the time, then-Vice President Joe Biden's son Hunter sat on the board of the company. Trump and his personal lawyer, Rudy Giuliani, have claimed – falsely – that the investigation was stopped as a result of political pressure applied by Joe Biden.

Until last week, Lutsenko publicly supported that assessment. But he has since aggressively walked back that support, saying in several media interviews that during his time as prosecutor general he saw no evidence of wrongdoing by either Biden.

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The impeachment probe has been rapidly widening.

Democrat congressional committees have subpoenaed U.S. Secretary of State Mike Pompeo and Giuliani for Ukraine-related documents deemed to be critical to the investigation. Pomepo took part in the call with Trump and Zelenksy, according to media reports. Giuliani took multiple trips to Ukraine. Pompeo on Tuesday accused House Foreign Affairs Chairman Eliot Engel, D-N.Y., of attempting to "intimidate, bully and treat improperly" State Department officials that Democratic committee chairmen have asked to depose in their impeachment inquiry centering on the growing Ukraine scandal.

Speaking during a press conference in Kiev on Tuesday, Zelensky told journalists he has "never met Giuliani."

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Olexiy Haran, a political scientist at the National University of Kiev-Mohyla Academy, said that the timing of the decision by Ukraine's SBI to accept the case against Lutsenko "looked strange" given that he is a figure in the U.S. impeachment inquiry.

But Haran cautioned against jumping to conclusions about whether the case is politically motivated because, he said, the SBI is obligated to open an investigation into alleged wrongdoing and doing so does not necessarily mean the case is credible.