Brazilian construction giant Odebrecht says it is filing for bankruptcy protection to restructure $13 billion in debt.

Odebrecht sent a statement Monday saying it filed the request for bankruptcy protection that same day. The debt restructuring is one of the largest ever filed in Brazil.

Odebrecht has been at the center of Operation Car Wash, the country's largest-ever corruption investigation that revealed a kickback scheme between politicians and construction firms that had become systematic in Brazil.

In December 2016, Odebrecht and one of its petrochemical subsidiaries pled guilty and settled with authorities in the U.S., Brazil and Switzerland on a $3.5-billion fine.