Michael Woodford, the British chief executive of Olympus who was ousted after raising "serious governance concerns", is to return to Japan for the first time since the scandal erupted and he fled the country fearing for his safety.
Mr Woodford will fly to Japan next week to meet the authorities investigating Olympus. On Thursday, he will provide evidence to the Tokyo Metropolitan Police, Japanese prosecutors and the Securities and Exchange Surveillance Commission. He said that the police had guaranteed his safety.
He told The Independent: "I'm not comfortable with returning, but I believe the authorities will safeguard me." Mr Woodford said that after the Serious Fraud Office (SFO) announced an official investigation he felt "it is important now that I communicate directly with the Japanese regulators".
Shortly after he was fired at a hastily convened board meeting last month, Mr Woodford left the country after warnings that he was under threat.
After scrutinising evidence Mr Woodford had passed on, the SFO announced on Wednesday that it would officially investigate the acquisition by Olympus of Gyrus, and the record $687m (£435m) paid to its financial advisers.
This has proved a frenetic time for Mr Woodford, who is to meet a delegation from the independent panel set up by Olympus to investigate the transactions next week.
He will then fly to the US to speak to investigators. The Federal Bureau of Investigation, the Department of Justice and the Securities and Exchange Commission are all scrutinising the company's transactions.
Olympus admitted this month that it had used payments relating to the Gyrus deal and three others to cover up losses at the group, a practice that had run for two decades. Mr Woodford has called for forensic accountants to inspect the books closely, saying: "We need to uncover the detailed truth."
This week it emerged that the company was to take a hard line on anyone involved in potential wrongdoing. Its newly installed president, Shuichi Takayama, said in an internal memo to staff: "We are preparing to take firm legal action, including criminal complaints, against any manager it finds responsible."
The company is under pressure to release its first-half results. If it does not publish the numbers before 14 December it will be delisted from the Tokyo Stock Exchange.