Dominique Strauss-Kahn, the former head of the International Monetary Fund, was summoned for questioning by the French police over suspicion of his involvement in organizing a prostitution ring and misuse of corporate funds, French media reported on Tuesday.

Strauss-Kahn, who arrived on Tuesday to the police station in the northern city of Lille, is under investigation over the so-called Carlton Affair for his alleged involvement of organizing orgies with prostitutes, most of which were held in French Carlton hotel. He is also suspected in similar events organized in Washington and Brussels.

According to French media, police also questioned Strauss-Kahn’s acquaintances, a businessman from Pas-de-Calais department, Fabrice Paszkovski and the former head of a local subsidiary of building giant BTP Eiffage, David Roquet. They are suspected of financing the parties from the company’s funds.

Strauss-Kahn was placed under arrest during the investigation. He may be charged with organizing a prostitution ring which could give him up to seven years in jail and a 375,000-euro fine.

In 2011, Strauss-Kahn, who was considered French President Nicolas Sarkozy's greatest rival at the upcoming presidential elections scheduled for March, was under invetigation for sexual assault on a hotel maid in New York.

The case was opened on May 14 after 32-year-old Nafissatou Diallo claimed Strauss-Kahn had assaulted her sexually at the Sofitel New York Hotel. Strauss-Kahn, 62, pleaded not guilty and said sexual contact with the maid was under mutual consent.