Tarak Bajpai was arrested by Mumbai Police last week, together with financial manager Ravi Khanna and technicians Rajeev Malhotra and Rais Khan, the Press Trust of India (PTI) reported. One of the firms early investors was also arrested.

Police made the arrests following a complaint from an investor who claimed to be owed thousands of pounds.

The company has attracted controversy for charging panellists upfront, while promising substantial returns for taking part in surveys and referring others to sign up too.

PTI reported police as saying that investments of around £183m have been made in Speak Asia by more than a million members. Detectives in the state of Andhra Pradesh have frozen the company’s accounts, according to the Times of India.

Industry associations Esomar and the Market Research Society of India have said that their codes prohibit researchers from asking respondents for money to take part – and that consumers should steer clear of any companies that request this.

News agency AFP quoted an emailed statement from the firm’s Indian CEO Manoj Kumar saying that it had “always offered complete and total cooperation to all authorities about its functioning and methodology” and that the developments were “a blot on our integrity”.

Research was unable to reach Speak Asia or Mumbai Police for further comment today.