Japan's Daihatsu Motor has stopped operations at an engine plant. The company had already announced that it would suspend production starting next week at all of its four car assembly plants, following the revelation of problems in safety test data.

Production lines stopped Friday at the engine factory in Fukuoka Prefecture, southwestern Japan, which is run by a subsidiary.

Daihatsu is a wholly-owned subsidiary of Toyota Motor. It has already stopped shipments of domestic models and will do the same for overseas markets.

A total of 174 cases of irregularities were found in data Daihatsu used to get safety certification for 64 different models.

Daihatsu is considering paying compensation to 423 of its parts suppliers for loss of sales.

But private research firm Teikoku Databank says that figure could rise to more than 8,000 if subcontractors and shipping companies are included.

Many of them are small and medium-sized firms. If the halt in production drags on, it could affect regional economies.

Daihatsu accounts for one-third of total mini-vehicle sales in Japan through about 30,000 dealerships.

Japanese Industry Minister Saito Ken says he instructed the company to appropriately respond to customers and clients, find the cause of the problem, and implement measures to prevent a recurrence.