Interpol is facing damaging allegations it colluded with China after the arrest of the Chinese former head of the global crime fighting body.

Lawyers representing the family of Hongwei Meng, detained by the Chinese authorities over alleged corruption in his homeland, have accused Interpol of compromising its ‘independence and political neutrality’ over the case.

In particular, they claim that Interpol worked closely with Beijing on a media strategy following Mr Meng’s detention.

They also accuse Interpol of infringing the ‘fundamental rights’ of Mr Meng and his family under international law.

Interpol's former president Hongwei Meng at the headquarters of Interpol in Lyon, France, in May 2018

Mr Meng's last WhatsApp message sent on September 25 says, 'Wait for my call,' at 12:26pm and is then followed by a knife emoji four minutes later

The allegations – made in a letter to the Secretary General of Interpol – raise the stakes following the controversial arrest of Mr Meng while on a visit to China from Interpol HQ in France in late September.

He was missing for several days before the Chinese authorities confirmed he had been detained over bribery allegations.

A letter of resignation, purporting to come from Mr Meng, was later sent to Interpol informing it of his decision to step down as president.

His wife, Grace, who is in hiding in France, has revealed that he sent her a text message with a knife emoji on the day he went missing and she remains ‘extremely’ concerned about his safety.

Her husband, whose whereabouts are unknown, is the latest high-profile target to be ensnared in China's sweeping anti-corruption campaign.

A number of top Chinese government officials, billionaires and even an A-list celebrity have vanished in recent months.

Mr Meng's high-profile position at Interpol was once seen as a prize for Beijing, but his arrest has raised questions about whom he might have angered or what he might have done to be targeted as part of President Xi's anti-corruption crusade.

It is not clear whether he had his Interpol computer with him when he was detained and if so whether it contained any operational secrets of value to China.

Grace Meng, who does not want to be identified, fears for her husband's safety as she consults her phone in the lobby of a Lyon hotel

In a separate letter this week to the Chinese ambassador to France, lawyers acting for Mr Meng and his family have asked for details about the charges he faces, the alleged evidence underpinning the charges and the location of his detention.

In a statement today, Mr Meng’s wife told Mail Online: ‘My twin boys celebrate their 8th birthdays tomorrow without their father. Tomorrow is also the second anniversary of my husband’s election to be President of INTERPOL. I hope that INTERPOL, and President Xi and Premier Li, respect my family’s rights and provide full answers to our letters of yesterday. I look forward to my family being safely reunited as soon as possible.’

Speaking yesterday a top Interpol official said its rules forbid him from probing into the fate of Mr Meng, who served as Interpol president for almost two years before he vanished during a trip to China.

Interpol's Secretary General Jurgen Stock said he ‘encouraged’ Chinese authorities to provide information about Mr Meng's location and legal status but can do no more.

‘We are a rules-based organisation. That is very important to understand,’ Mr Stock said, adding that the role of Interpol is ‘not to govern over member states’.

‘There is no doubt this is a very regrettable situation. But on the other hand, we have to ensure day-to-day operations ... continue,’ he went on.

Confirming Mr Meng’s arrest last month, China's Public Security Ministry said the probe was ‘correct, wise and shows the determination of [President Xi]'s administration to continue its anti-corruption drive.'

Then China's Vice Minister of Public Security, Mr Meng makes a campaign speech at the 85th session of the general assembly of Interpol, in November 2016, in Bali, Indonesia

Interpol is the global policing agency that co-ordinates between police forces around the world, including searches for missing and wanted persons.

Its general secretariat oversees the day-to-day work of the 192-member organisation, with the role of the president largely ceremonial.

Following confirmation of his arrest last month, Interpol urged China to clarify Mr Meng's status, saying it was concerned about the well-being of its president. There has been no word from him on the charges he faces.

Mr Meng, 64, rose through the ranks of China's feared public security apparatus before being caught himself in President Xi Jinping's no-holds-barred campaign against corruption.

His arrest marks the end of a 14-year career overseeing various top public security bureaus in China, including the country's armed police force.

Born in 1953 in northeastern Heilongjiang province, he joined the Communist Party of China in his early 20s after graduating from Beijing University with a bachelor's degree in law.

As vice security minister, Mr Meng has been entrusted with a number of sensitive portfolios, including the country's counter-terrorism division, and he was in charge of the response to violence in China's fractious north-western region of Xinjiang.

At Interpol, he was expected to serve a four-year term until 2020. His election in 2016 had raised concerns among human rights groups, which feared that Beijing would use the organisation to round up Chinese dissidents overseas.

Today two law firms representing Mr Meng and his family said: ‘Lindeborg Counsellors at Law and Marsigny Avocats confirm that they have sent letters to INTERPOL and the Ambassador of the People’s Republic of China in France on behalf of Mr Hongwei Meng and his family.

'Mr Hongwei Meng and his family look forward to receiving full responses.’

Interpol has been asked to comment.