Italian prosecutors are investigating the wife of Eni's chief executive as part of a wider probe into allegations of corruption involving the oil and gas major in Congo Republic, a prosecution document seen by Reuters showed.
State-controlled Eni has previously said it was under investigation by Milan prosecutors for corruption in Congo Republic from 2013 to 2015. The company has denied the allegations.
Prosecutors told a court this year that five people were being probed, including Eni's former head of sub-Saharan Africa, who denied any wrongdoing.
Milan prosecutors have now added Marie Magdalena Ingoba, the wife of Eni CEO Claudio Descalzi, to their list of suspects, according to the prosecution document seen by Reuters.
A person with direct knowledge of the investigation confirmed the addition of Ingoba's name to the list.
The corruption case revolves around agreements signed by Eni's subsidiary in Congo with the African nation's ministry of hydrocarbons for exploration and production permits. It also revolves around partners Eni picked for its contracts.
Prosecutors issued search warrants for Descalzi's and Ingoba's homes in Italy on Thursday as part of a separate probe into the couple over allegations of conflicts of interest in Congo.
Descalzi said on Thursday he rejected those allegations, while Ingoba could not be reached for comment at that time.
Asked about the investigation into Ingoba for alleged corruption, Nadia Alecci, a lawyer who had been acting for her, told Reuters on Friday she was no longer representing Ingoba and said she did not know the name of her new lawyer.
She said Ingoba, who is a national of Congo Republic, was in Japan and said she could not provide any contact details.
A spokesman for Eni declined to comment on Friday and said he could not forward a request from Reuters to Ingoba seeking comment.
Eni, which Descalzi has led since 2014, has denied any wrongdoing in Congo and has said investigations it outsourced to independent, third-party consultants had revealed no evidence of offences committed by Eni managers or employees.
(Writing by Silvia Aloisi; Editing by Edmund Blair and Mark Potter)