The Interpol chief who went missing last week has resigned his post after it emerged he is being questioned by Chinese authorities, the international police agency said.

The announcement came shortly after China confirmed it is holding Meng Hongwei, who has been missing for days, and his wife revealed he sent her an image of a knife before he disappeared as a sign that he was in danger.

"Today, Sunday 7 October, (at) the Interpol General Secretariat in Lyon, France received the resignation of Mr Meng Hongwei as President of Interpol with immediate effect," Interpol said in a statement late on Sunday. It did not give a reason for the resignation.

The agency said South Korean national Kim Jong Yang would becomes its acting president, while it would appoint a new president at a November 18-21 meeting of the organisation in Dubai.

Earlier, China's new anti-corruption body said authorities were investigating Mr Meng, who is also a vice minister of public security in China, for suspected violations of the law.

The National Supervision Commission, which is also the ruling Communist party’s watchdog for political disloyalty, did not specify what the alleged violations were.