SAO PAULO (AP) — Former Brazilian President Luiz Inacio Lula da Silva has been subpoenaed as part of an investigation into a suspected money laundering scheme involving an apartment he once thought of buying, the Sao Paulo state prosecutor's office said Friday.

The office of prosecutor Cassio Conserino said Silva and his wife, Marisa Leticia, would be questioned Feb.17.

Earlier this week, prosecutors said they were investigating whether some of the money from the big corruption scandal buffeting state owned-oil company Petrobras was laundered through illegal real estate transactions involving the OAS construction company.

OAS constructed the building where Silva considered buying the apartment. Conserino's office said there were "indications that there was an attempt to hide the identity of the apartment's owner, which if proven would mean the crime of money laundering had been committed."

Silva has said that he and his wife had an option to buy the apartment in the coastal city of Guaruja but they never purchased it. The Sao Paulo-based Lula Institute said on its website that the prosecutor's suspicions of alleged concealment of assets by Silva were unfounded and frivolous.

Prosecutors have alleged that over $2 billion was paid in bribes by businessmen to obtain Petrobras contracts for projects that subsequently ballooned in costs.