A cement bunk, a shower, a cold water shower and a hole in the floor as a toilet. This is a prison cell in Bangu 9, in the humble neighborhood of Rio de Janeiro. Eike Batista (60), the Brazilian entrepreneur who became the seventh richest man in the world, with a net worth of about 28 million euros barely five years ago, is now in prison for bribing politicians.

“I’m going to respond to the Justice as it is my duty,” Batista said to Globo TV at John F. Kennedy airport, before departing to Rio de Janeiro, where he was arrested as soon as he landed. “It’s time to help clean things up.”

Batista is accused of participating in a vast corruption scheme. Specifically, Batista alleged paid $16.5 million to the former Governor of Rio de Janeiro, Sérgio Cabral, who has been incarcerated since November, accused of running a corruption ring.

Until five years ago, Batista had a net income that exceeded $30 billion. That made him the seventh richest man in the world and the richest in Brazil, according to Forbes magazines. He controlled Grupo EBX, which was a large conglomerate with businesses in shipbuilding, mining, the oil industry and logistics. Later, his company suffered a downfall. He lost more than $27 billion after that. Bloomberg reported in January 2014 that Batista “has a negative net worth.” Forbes and Folha de S. Paulo quoted Batista in September 2014 stating that his negative net worth was – $1 billion.

Batista prison is part of a sweeping investigation into corruption at state-owned oil company Petrobrás, known as Operation Car Wash, that has implicated many of the country’s leading businessmen and politicians.