Carlos Ghosn's wife arrives at Tokyo District Court for questioning

The wife of ousted Nissan boss Carlos Ghosn arrived at Tokyo District Court, Kyodo News reported on Thursday, where she is expected to be questioned by prosecutors.

Carole Ghosn returned to Japan on Wednesday, days after she left the country to seek help from the French government, and was to be questioned by authorities, a source with knowledge of the matter told Reuters.

Prosecutors last week arrested the former Nissan chairman for the fourth time on suspicion he tried to enrich himself at the cost of $5 million to the automaker.

Authorities had also wanted to question Carole Ghosn on suspicion that her husband had siphoned off payments through a company where she is an executive to purchase a yacht and a boat, public broadcaster NHK has reported.

Carlos Ghosn, a French, Lebanese and Brazilian citizen, rejects all the charges against him and says he is the victim of a boardroom coup.

The Nikkei reported that his wife had arrived back in Japan at Tokyo's Haneda airport on Wednesday, quoting her as saying she wanted to tell a court that there was "absolutely nothing illegal".