RIO DE JANEIRO, Jan. 26 (Xinhua)-- The Brazilian Justice Ministry has ordered an arrest warrant against millionaire Eike Batista, formerly the eighth richest man in the world, who is thought to have fled the country, official sources announced Thursday.

Operation Efficiency is investigating a suspected money laundering ring, led by former Rio de Janeiro governor Sergio Cabral, who is accused of having stashed over 100 million U.S. dollars during his office period from 2007 to 2014.

Seven people have been arrested in the latest round of this investigation, including Flavio Godinho, Batista's former right-hand man and the vice-president of the Flamengo football club.

Cabral himself was arrested on Nov. 17, accused of embezzling millions of dollars and of charging a 5 percent fee for public contracts allocated during his time as governor.

According to the police Thursday, Batista allegedly paid 16.5 million U.S. dollars to Cabral in order to obtain a number of contracts.