Tomasz Szmydt, a judge of the provincial administrative court in Warsaw, left Poland for Belarus and said he intends to apply for political asylum due to his "disagreement" with the Polish government's policies.
Tensions between Poland, a NATO country, and Russian ally Belarus have surged following Russia's full-scale invasion of Ukraine.
"I express my protest to the Polish authorities who, under the influence of the U.S. and Great Britain, are leading the country to war," Szmydt said at a press conference in Minsk on May 6.
"The Polish nation supports peace and good neighborly relations with Belarus and Russia. That's why I'm in Minsk and I'm ready to tell the truth."
Szmydt claimed that he was subject to political persecution and intimidation by Polish authorities for his pro-Russian viewpoints and that he was "forced to leave" Poland.
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Polish officials denounced Szmydt as a traitor following the press conference.
"I don't know what Tomasz Szmydt is running away from," Stanislaw Zaryn, a Polish presidential adviser, said on X.
"In the past, similar acts were performed by those who were afraid of responsibility for their actions in Poland. No one in their right mind runs away to Belarus to become a puppet in the hands of Putin and Lukashenko."
Zaryn said that he expects the former judge to begin a new career as "a propaganda star for Russia and Belarus."
Poland's Internal Security Agency said it had opened an investigation into the scope of classified information Szmydt may have had access to during his time as a judge.
Belarus, led by dictator Alexander Lukashenko, is a close ally to Russia and has provided extensive support to Moscow's war in Ukraine. The Belarusian army regularly conducts military drills along its border with Poland and other EU countries.
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