Jakarta. The Supreme Audit Agency, or BPK, lodged a defamatory complaint to the National Police on Monday against businessman Benny Tjokrosaputro, the key suspect in a major graft scandal at state insurer Jiwasraya.

The complaint was made after Benny told reporters last week that BPK leaders have been protecting Bakrie Group from being dragged into the case and that they were "the cronies" of the business conglomeration.

"We reported Benny Tjokrosaputro to the Criminal Investigation Agency for defamation. It's clear that [Benny’s statements] constitute slanderous remarks and are subject to a criminal investigation," BPK Chief Agung Firman Sampurna told reporters at the National Police headquarters in South Jakarta.

Agung denied Benny's allegations that the agency had protected Bakrie Group – owned by politician and media mogul Aburizal Bakrie – or any other individuals and business entities when it was helping the Attorney General's Office in the investigation into Jiwasraya.

The BPK has provided an official estimate of financial losses to the state incurred by the graft scandal. It said in March that crooked investments by Jiwasraya had inflicted Rp 16.8 trillion ($1.2 billion) in state losses.

"Our calculation on the state losses has been finalized, but it still allows prosecutors to continue their investigation and name more suspects," Agung said.

Benny, the president director of property firm Hanson International, launched his verbal attack on the BPK leaders on the sidelines of his court hearing in Jakarta last Wednesday.

He said his indictment implied as if he had been in command of all Jiwasraya's bad investments, including in manufacture and infrastructure firm Bakrie & Brothers.

"Think about this: there was a company called Bakrie & Brothers – how could I be responsible for everything?" Benny told reporters.

"The BPK chairman and the deputy chairman are covering things up. It's obvious they're Bakrie's cronies," Benny said.

Benny, who was detained by prosecutors in January, said the troubled insurer had been in the red since 2006 when Bakrie & Brothers was already in the company. He claimed he was just a scapegoat in the case.

Prosecutors initially named six suspects of mostly Jiwasraya's former top executives in the graft case. As the investigation developed, the AGO announced on Friday that 13 investment management companies had been named as "corporation suspects" and a Financial Services Authority (OJK) executive as a new individual suspect.