Brazilian police on Thursday arrested the head of the country's national Olympic committee.

Carlos Arthur Nuzman stands accused of corruption, money laundering and criminal association as part of a probe into a cash-for-votes scheme to influence the International Olympic Committee (IOC) vote that chose Rio de Janeiro for the 2016 games.

Nuzman's home was raided last month and documents taken into police control.

Marcelo Bretas, the federal judge who issued the arrest warrant, said that new evidence indicated Nuzman's role in the alleged vote buying scheme was "more relevant" than previously believed.

Read: Rio's Olympic legacy: Corruption and people power

A lawyer of Nuzman, Nelio Machado, called the allegations "unfounded."

Leonardo Gryner, the Rio 2016 committee's chief operating officer, was also taken into custody, Brazilian newspaper O Globo reported.

Nuzman is accused of helping to buy the vote of disgraced Senegalese IOC member Lamine Diack — formerly president of the International Association of Athletics Federations.

Unfair play

The plot allegedly involved a payment of some $2 million (€1.7 million) to Diack's son before the 2009 vote in which Rio beat out bids from Chicago, Madrid and Tokyo to host the Games.

Bretas said that Nuzman's wealth increased roughly four-fold between 2006 and 2016. He also accused the former volleyball player of failing to declare assets until after the so-called Unfair Play investigation began. Among the hidden assets were 16 kilos of gold in a Swiss bank, he said.

The IOC said it would cooperate with the investigation and asked Brazilian authorities to share any information about alleged vote buying.

"Given the new facts, the IOC Ethics Commission may consider provisional measures while respecting Mr. Nuzman's right to be heard," the IOC said. Nuzman is an honorary member of the IOC.

In June, former Rio governor Sergio Cabral was sentenced to 14 years in prison for bribery and money laundering related to the 2016 Games.  Authorities say he was the mastermind behind the vote buying plot.

Businessman Arturo Soares, a contractor for Cabral's administration, is alleged to have delivered the payments.

cw/msh (AFP, dpa, Reuters)