(Adds details and background)
TOKYO, Dec 6 (Reuters) - Tohoku Electric Power Co, Japan's fourth-biggest electric utility by sales, said on Wednesday it uncovered cases of data tampering, another company owning up to shortcomings that have undermined faith in Japanese industrial standards.
The utility, which provides electricity to customers in a region north of Tokyo, said it found specifications data on electricity transmission pylons had been tampered to show they met the company's internal standards.
No safety issues have risen and the company has taken steps to reinforce the pylons where needed, a spokesman said.
The company joins Kobe Steel Ltd, Mitsubishi Materials Corp and Toray Industries Inc, which earlier reported cases of data tampering in products sold to customers.
While no safety issues have been identified, the widening scandal has undermined faith in Japan's manufacturing prowess and roiled global supply chain.
Tohoku Electric said it discovered the tampering in October and has checked about 270 pylons in the same area. It has not been able to check all pylons as snow has made it difficult to access some areas.
The company informed the Ministry of Economy, Trade and Industry on Wednesday and has set up a committee to look into the causes of the data tampering and to recommend responses.
(Reporting by Yuka Obayashi; Writing by Aaron Sheldrick)