Cosmo Oil Co. has revealed additional cases of failing to inform authorities of gas leaks and other accidents at its refineries.

Seven accidents took place between June 1998 and April last year at Cosmo facilities in Chiba, Mie and Osaka prefectures. No one was injured in the mishaps, Cosmo said Thursday.

The announcement dealt a further blow to the major oil distributor after it revealed last month a hydrogen gas leak in December in Chiba.

The Tokyo-based company had neglected its reporting obligation to local governments.