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By Ricardo Brito and Ana Mano
BRASILIA/SAO PAULO, Sept 14 (Reuters) - Brazilian police raided the home of Agriculture Minister Blairo Maggi on Thursday in a corruption investigation linked to his time as a state governor, adding to the graft scandals rocking President Michel Temer's government.
Last month the Supreme Court opened a bribery probe into Maggi's role in a scheme known as "mensalinho," a payment of a monthly stipend to lawmakers in exchange for political support in his home state of Mato Grosso. He served two terms as governor there between 2003 and 2010.
According to a person with direct knowledge of the matter, the raid was linked to a plea deal by former Mato Grosso state governor Silval Barbosa, who accuses Maggi of participating in the corruption scheme.
Barbosa was Maggi's vice-governor, replacing him in the top job in 2010 when Maggi resigned to run for a seat in Brazil's Senate. Barbosa was subsequently elected to a four-year term that ended in 2014.
Maggi denied any wrongdoing, claiming in a statement that Barbosa "lied" in his plea bargain testimony.
"I never authorized any illegal actions while in office nor have I obstructed justice," Maggi said.
Maggi is a billionaire who was once Brazil's largest soybean producer. His family firm Amaggi SA runs large farms in Mato Grosso and operates a commodity trading business that competes in Brazil with global firms like Archer Daniels Midland Co , Cargill Inc and Bunge Ltd.
Mato Grosso, where federal police said they served search warrants in nine cities, is a major producer of grains and cattle. Raids were also conducted in São Paulo and Brasília, the police said in a statement.
The probe marks the latest blow to Temer's administration, whose economic reform agenda has been repeatedly thwarted by graft investigations that have targeted top officials, including the president. Temer has denied any wrongdoing. (Reporting by Ricardo Brito in Brasilia and Ana Mano in São Paulo; Writing by Guillermo Parra-Bernal and Ana Mano; Editing by Brad Haynes and Paul Simao)