TOKYO, Nov. 30 (Xinhua) -- The Tokyo District Court on Friday approved a request from prosecutors to extend the detention of former Nissan Motor Co. Chairman Carlos Ghosn for a further 10 days after his arrest last week on allegations of gross financial misconduct.

Until the latest extension was approved by the court, Ghosn, 64, and co-conspirator Greg Kelly, a former Nissan representative director who was arrested along with Ghosn for alleged financial improprieties, were scheduled to be released Friday.

Ghosn's detention in a solitary cell could be extended further, sources close to the matter said Friday, as Japanese law stipulates that the limit a suspect can be held without charge is 23 days if an arrest warrant was issued by police and 22 days if it was issued by prosecutors.

In theory, as new charges and fresh warrants are served, as long as they are approved by a court, a suspect can be held in detention in Japan indefinitely.

Ghosn, a heavyweight in the global auto industry, was arrested on Nov. 19 on suspicion of reporting only about five billion yen (44 million U.S. dollars) of nearly 10 billion yen (88 million U.S. dollars) in earnings over the five years to March 2015 in Nissan's securities reports.

Sources close to the matter believe that Ghosn ordered Kelly, his close aide and potential partner in crime, to ensure that Nissan's financial records showed he earned just one billion yen (8.8 million U.S. dollars) a year.

This amounts to 50 percent of his actual remuneration, the sources have highlighted.

Following his retirement, Ghosn, who holds Brazilian, French and Lebanese citizenship, was intending to receive the surplus funds as fees for consultancy, sources said.

Ghosn has admitted to the Tokyo prosecutors his remuneration was not fully reported in the securities reports to be submitted to Japanese regulators.

He has maintained, however, that the reports were not intentionally doctored, sources close to the investigation said, and claims he did not have to report some of his earnings on payments that have yet to be settled.

He also said that one of the reasons he did not report the full amount was that he did not want his workers to become demotivated as employees on hearing the details of his substantial pay package.