(Bloomberg) -- Czech billionaire Prime Minister Andrej Babis is facing renewed pressure over fraud allegations after his son claimed he’d been lured to Crimea and abducted to hide him from the probe.

Babis, a chemicals, agriculture and media magnate with an estimated fortune of $3.5 billion, is a polarizing figure in the European Union’s eastern wing, clashing with the bloc over migration and efforts toward further integration among its members. Despite the police investigation into his activities before he entered government, he remains the most popular politician in the former communist country and leads a minority ruling coalition.

An opposition party threatened to call a no-confidence motion against the government after the Seznam.cz website broadcast a video of his son saying that people working for his father had lured him to Crimea and held him there against his will. Andrej Babis Jr. is a central figure in the investigation into the alleged misuse of EU funds at a recreation center that once belonged to Babis’s business empire. He was named by his father as one of the owners.

Read More: Czech Parliament Strips Billionaire Premier of His Immunity

Babis said Tuesday his son wasn’t abducted and that police had already concluded no crime had been committed. He said that his son, who lives in Switzerland with his mother, is being treated for mental illness. Andrej Babis Jr., an adult son from the prime minister’s first marriage, was in the Black Sea peninsula seized by Russia from Ukraine in 2014, but is now back in Switzerland.

“I reject this manipulation and egregious pressure from journalists on law enforcement authorities,” Babis, who rejects comparisons to U.S. President Donald Trump in Czech media for his wealth, confrontational governing style and anti-immigration stance, said on his Facebook page. “It is regrettable to see this witch hunt on my family.”

The Social Democratic Party, Babis’s coalition partner, said it expects Babis to answer questions about the case, stopping short of drawing political implication for the government. The opposition Christian Democrats said they were considering whether to call a confidence motion against Babis’s administration, which lacks a majority in parliament and survives with the support of the Communist party.

Babis rejects the allegations of wrongdoing in the fraud case and has denounced the charges as an attempt by his rivals to torpedo his political career. Parliament stripped him and one of his closest allies of immunity from prosecution earlier this year. Police said they will look into the veracity of the video, including questioning the reporters.

To contact the reporter on this story: Peter Laca in Prague at placa@bloomberg.net

To contact the editors responsible for this story: Balazs Penz at bpenz@bloomberg.net, Michael Winfrey, Andras Gergely

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