HONG KONG, Oct. 8 (SCMP) -- The Chinese head of Interpol – who vanished last month after returning to his homeland – was under investigation for possible criminal activity, China announced late on Sunday, as the world police organisation said he had resigned.

The revelations came as Meng Hongwei’s wife voiced concern for his life after receiving a final text message from his phone with a knife emoji.

Meng, 64, was reported missing last week by his wife in Lyon, France, where Interpol is based. Grace Meng said she had not heard from her husband since September 25, according to a statement from the French interior ministry.

While Beijing did not provide any further information about Meng’s detention, analysts said that the fact it was willing to jeopardise its diplomatic relations by snatching a high-profile official in such a way suggested the stakes were high. Meng is also a Chinese deputy public security minister.

The National Supervisory Commission said in an unusually terse statement just before midnight local time that Meng was being investigated for suspected violations of unspecified state law, confirming the Post’s report last week.

Interpol said in a statement on Sunday that Meng had resigned “with immediate effect”.

In Lyon, Grace Meng spoke to the news media just before Beijing issued its statement, pleading with national governments to intervene, saying she feared that her husband’s life was in danger, Agence France-Presse reported.

Meng said the last social media message she received from her husband came on September 25, saying “wait for my call,” followed by a knife emoji.

“This matter belongs to the international community,” Meng told a press conference in English. “I’m not sure what has happened to him.”

A source told the South China Morning Post on Friday that Meng was “taken away” for questioning by discipline authorities “as soon as he landed in China”.

But the midnight statement by the NSC did not mention if Meng was suspected of breaking any Communist Party rules, a form of words the anti-corruption agency usually adopts to refer to its investigations.