TOKYO, Dec 21 Reuters Toyota Motor shares slumped on Thursday as Japan39;s transport ministry inspected a subsidiary over safety concerns dating back decades and as the world39;s topselling automaker separately also announced a recall of 1.1 million vehicles.

Shares in Japan39;s biggest automaker were down 3.8 by the end of morning trading.

A day earlier, Toyota39;s smallcar unit Daihatsu Motor said it would halt shipments of all of its vehicles for an indefinite period after discovering more safetyinspection irregularities.

Daihatsu said that an independent committee had found issues involving 64 models, including almost two dozen sold under Toyota39;s brand.

The panel had been investigating the unlisted car maker after it said in April that it had rigged sidecollision safety tests carried out for 88,000 small cars.

Daihatsu said on Wednesday it did not know when it would resume shipments, but that the impact on its earnings would be substantial.

Daihatsu had nothing to add when contacted by Reuters on Thursday.

Japan39;s transport ministry said it would consider administrative penalties against Daihatsu, including potentially revoking its production certification, depending on the outcome of its investigation.

Chief cabinet secretary Yoshimasa Hayashi told reporters this is an extremely regrettable case that undermines the trust of automobile users and is a misconduct that affects the very foundation of the automobile certification system.

Toyota said on…