Two Greek investigative magistrates have asked officials in Belgium, France, The Netherlands and Cyprus to release bank account details of Greece’s former defense minister Yiannos Papantoniou.

He had been charged with laundering 2.8 million euros ($3.31 billion) in Swiss Francs he allegedly pocketed in exchange for securing a contract in 2003 to upgrade six Hellenic Navy frigates.

The Greek fraud squad is probing corruption in past public procurement deals and traveled to the Hague recently to try to get the additional bank information and lodge complaints against Papantoniou, said Kathimerini.

The requests were submitted by Iliana Zamanika and Giorgos Evangelou while the paper said another European Union country it didn’t name was also looking into the frigates contract, one in a long line of scandals at the ministry.

The former minister and his wife Stavroula Kourakou are being held in Attica’s high-security Korydallos Prison, after judicial authorities deemed them a flight risk as they rent a second home in Switzerland and have bank accounts there.

Kourakou has submitted a request for her release from pre-trial detention, which is being examined by judicial authorities.

A case file against former Papantoniou who served the now-defunct PASOK Socialists is also probing allegations of repeated passive bribery, tied to reported kickbacks related to the C4I security system for the Athens 2004 Olympic Games.

Among the documents included in the file is nine pages of sworn testimony by Evangelos Vasilakos, former director general of the Defense Ministry’s General Directorate of Defense Armaments and Investment from April 2006 to October 2010, Kathimerini reported.

The charge refers to an alleged bribe in excess of 150,000 euros ($170,000) which the former minister is believed to have taken for the system’s acquisition and installation.

Earlier, Papantoniou denied charges of money laundering during a lengthy deposition before a corruption prosecutor during which the state charged he had cost 400 million euros ($458.37 million) in damages in 2003 over the Navy frigate armaments program.

Papantoniou reportedly claimed had the procurement contract not been signed, he would have been accountable for serious offenses and would have harmed the interests of the state but he has denied everything.