The scandal at Mitsubishi Motors could date back a quarter of a century, it was reported this morning, as the troubled Japanese car maker announced it was setting up a special committee to investigate wrongdoing.
In a statement issued this morning, Mitsubishi said: "Mitsubishi expresses its most sincere apologies to all of our customers, shareholders, and stakeholders for any inconvenience or concern caused by this occasion.
"The board of directors decided to establish a special investigation committee consisting of only external experts" to further investigate the claims.
Read more: Mitsubishi admits wrongdoing
News outlet Bloomberg reported that the committee, made up of three former prosecutors, will investigate whether fuel efficiency data had been rigged going back as far as 1991.
When the scandal broke, the company initially said that it had been flouting Japanese rules since 2002.
Shares in the company dropped a further 9.6 per cent during Tuesday trading, taking shares since the scandal broke 49.7 per cent lower