OSAKA – A plan to repurpose 150 electric buses used in last year’s World Exposition in Osaka to transport visitors has been put on hold after safety concerns emerged over the vehicles, the city said Wednesday.

The fleet had cost about 7.5 billion yen ($47 million), of which more than 4 billion yen came from subsidies from the central government, Osaka Prefecture and Osaka City.

Osaka Metro Co., which offers subway and bus services in the city area, has planned to use the buses on regular routes and in autonomous-driving trials following the six-month expo, which ended in October and attracted over 25 million visitors.

The buses were purchased from EV Motors Japan Co., based in Kitakyushu in Fukuoka Prefecture. The Land, Infrastructure and Transport and Tourism Ministry had inspected the company in October after repeated operational troubles.

The buses are currently stored on the premises of Osaka Metro, some of which are undergoing safety checks.

An official of Osaka City, the sole shareholder of Osaka Metro, said the company may seek a refund of the purchase funds if safety cannot be confirmed.

AloJapan.com