PARIS (AP) — French police have detained a Russian lawmaker and tycoon in southern France as part of a probe into suspected laundering of tax fraud proceeds, a French prosecutor said Tuesday.

The prosecutor told The Associated Press that Suleiman Kerimov, a Russian billionaire who has a seat in the upper house of Russian parliament, was arrested at the airport in the Riviera city of Nice on Monday night.

Kerimov was put in custody for questioning in the case, Nice prosecutor Jean-Michel Pretre said.

Russia's Foreign Ministry said Tuesday night it has notified France that Kerimov has diplomatic immunity.

Kerimov shot to fame in the soccer world in 2011 when he bought Russian club Anzhi Makhachkala and went on a spectacular spending spree.

Kerimov's Anzhi signed stars including Brazilian defender Roberto Carlos and Cameroonian forward Samuel Eto'o in a bid to become a top European club almost overnight.

However, Kerimov abruptly slashed his financing for the team in August 2013 with little explanation and sold off its stars, reverting Anzhi back to a minor provincial club. Kerimov sold Anzhi last year.

The controversial 51-year-old oligarch, who made a fortune by investing in struggling companies, represents the Caucasian Republic of Dagestan — where he was born — in the Council of the Russian Federation, the upper house of Parliament.

Kerimov's fortune is estimated at $7.4 billion by Forbes magazine.