Mitsubishi Motors have recently come under the spotlight after admitting that they had manipulated fuel economy tests on its own brand and Nissan cars in order to have the results reflect slightly better than they would have.
Officials were brought in to search the plant in the central Japanese city of Okazaki after the Japanese company had admitted that employees had adapted data to favourable mileage rates on more than 600,000 vehicles.
The announcement reminds people of the emissions-testing scandal at German giant Volkswagen not too long ago, furthering more doubt on the quality of world testing regimes.
A deadline of 27 April has been set for Mitsubishi Motors to hand over the report on the inaccurate testing and is being treated as an "extremely serious case".
The chief cabinet secretary of Japan, Yoshihide Suga, has said that they "would like to reveal the extent of the inaccuracies as soon as possible" and that they "will deal with the situation in a strict manner and would like to make sure of the safety of the cars".
The scandal involved 157,000 of Mitsubishi's own brand passenger cars and 468,000 vehicles that were produced for Nissan, who had no knowledge of the false report.
UK managing director, Lance Bradley, noted that the cars in question (Mitsubishi ek Wagon, Mitsubishi eK Space, the Nissan Dayz and Nissan Roox) are "only sold in the Japanese domestic market" and that there "is no evidence to suggest that UK and European modes are affected".
An auto analyst named Akira Kishimoto at JPMorgan told Reuters that the scandal could cost Mitsubishi more than 50n yen (£313.8m) which include payments to consumers, money spent on replacing parts and compensation the company would have to pay to Nissan.
This isn't the first time Mitsubishi's name has been mentioned in the same sentence as scandal, as the car giant struggled to regain its positive reputation in the early 2000s due to cover ups of issues such as faulty brakes, problems with clutches and fuel tanks that were reported to be falling off.