RIO DE JANEIRO (AP) — Brazil's presidential palace announced Monday that Justice Minister Jose Eduardo Cardozo is leaving his post, a change that comes after political allies criticized his handling of a big corruption scandal.

Hours before the announcement, a group of police chiefs expressed "extreme concern" at the expected departure of Cardozo, one of President Dilma Rousseff's closest allies, charging it was a result of political pressure to limit their investigations.

A news release from the presidential office said Cardozo was becoming attorney general — a post that is not involved with criminal investigations and prosecutions. Bahia state prosecutor Wellington Cesar Lima e Silva will be the new justice minister.

Officials in the governing Workers' Party had complained about Cardozo's refusal to limit the scope of "Operation Car Wash," a corruption investigation that has implicated dozens of senior politicians as well as some of the country's top business executives.

In particular, party members have been angered by investigations into former President Luiz Inacio Lula da Silva, who is accused of concealing benefits from construction companies involved in a kickback scandal.

On Saturday, at an event to mark 36 years of the Workers' Party, Silva attacked the media and opposition, accusing them of spreading "lies, leaks and accusations of criminality." He also said he would be willing to run again for president in 2018 as the candidate of the Workers' party "if necessary."

In what was seen as a sign of Rousseff's deteriorating relationship with her predecessor, the president did not attend the Worker's Party event, telling reporters that "government is one thing, parties are another."

Cardozo has been at the Justice Ministry since the start of Rousseff's first term in January 2011 and is considered one of her closest advisers.

Claudio Couto, a professor of political science at the Fundacao Getulio Vargas, said that while Cardozo's departure was unlikely to have an impact on the corruption investigation, it would leave the president more isolated at a time when she is fighting an impeachment effort.

"It's a tragic situation," he said. "She has to try to please the party because she needs its support, but every time she does so she undermines what little credibility she has left."