A total of 215 manufacturing plants in Thailand affiliated with 139 Japanese listed firms have been damaged by the flooding there, a private research agency said in a recent survey.

Of the 139 companies, 81 were in the electronics business and 71 in the automotive business, with several involved in both sectors, Tokyo Shoko Research said, indicating the engines of Japan's manufacturing industry are being heavily affected.

Of the damaged plants, 173 were forced to suspend operations and seven altered their production schedules. Among the idled plants, 95 were flooded, 41 shut down to ensure employee safety and 28 were told to evacuate.

Tokyo Shoko also said it has confirmed that at least 96 unlisted Japanese firms are operating in seven industrial parks that took heavy damage from the water.