Interpol demanded an official “clarification” from China on the whereabouts of its missing police chief Saturday, after reports said he was detained for questioning on arrival in his homeland.

Beijing has remained silent over the mysterious disappearance of Meng Hongwei, who was last seen leaving for China in late September from the Interpol headquarters in Lyon, southeast France, a source close to the enquiry told AFP.

His wife has since reported him missing.

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“Interpol has requested through official law enforcement channels clarification from China’s authorities on the status of Interpol President Meng Hongwei,” Jurgen Stock, the secretary-general of the international police body said in a statement.

“Interpol’s General Secretariat looks forward to an official response from China’s authorities to address concerns over the President’s well-being.”

It is the latest high-profile disappearance in China, where a number of top government officials, billionaire business magnates and even an A-list celebrity – Fan Bingbing – have vanished for weeks or months at a time.

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The Ministry of Foreign Affairs did not respond to a request for comment from AFP.

But news of his absence was swiftly followed by speculation that the 64-year-old Meng – who also serves as a vice-minister of China’s Ministry of Public Security – had been swept up in Beijing’s secretive anti-corruption campaign.

Citing an anonymous source, the South China Morning Post said authorities from the country’s disciplinary commission had snatched Meng upon arrival in Beijing.

China’s recently established National Supervisory Commission holds sweeping powers to investigate the country’s public servants with few requirements for transparency.

While the law requires authorities to inform family members of a detention, it makes exceptions for cases involving national security, terrorism, or concerns over destruction of evidence or witness tampering.

People have been known to disappear into the commission’s custody for weeks or even months without a word.

It is not clear why Meng – the first Chinese president of Interpol – would be under investigation.

Chinese president Xi Jinping has presided over a popular anti-graft drive since coming to power in 2012 that has punished more than one million officials, with critics comparing it to a political purge.

Meng rose up the ranks of the country’s domestic security apparatus when it was under the leadership of Zhou Yongkang, a rival to Xi and the highest-ranking official to be brought down on corruption charges.

Zhou – who was sentenced to life in prison in 2014 – was subsequently accused of conspiring to seize state power and authorities have continued working to root out his influence.

He appointed Meng vice security minister in 2004.

In the role Meng has been entrusted with a number of sensitive portfolios, including heading up the country’s counter-terrorism division, which saw him in charge of the response to several major incidents in China’s fractious western region of Xinjiang.

Critics of Meng’s 2016 election to Interpol’s presidency said he would use the position to help China target dissidents abroad under the guise of pursuing corrupt officials.

Interpol has downplayed the concerns, saying the president has little influence over the organisation’s day-to-day operations, which are handled by secretary-general Stock, a German.

The Chinese effort to track down corrupt officials abroad, known as Operation Fox Hunt, has led to claims in some countries that Chinese law-enforcement agents have been operating covertly on their soil without the approval or consent of local authorities.

China currently has 44 outstanding red notices, mostly related to murder, intentional injury and drug smuggling, according to Interpol’s web site.

During Meng’s tenure, Interpol issued a red notice for fugitive Chinese billionaire real estate tycoon Guo Wengui, who threatened to reveal corruption at the country’s highest levels.

Authorities in China and Hong Kong have accused Guo, who resides in the United States, of laundering billions of dollars among other crimes.