The accident happened on a highway in the Indian portion of Bengal, the Press Trust of India reported.
Several of the injured were reportedly in critical condition.
Police said initial indications were that the driver lost control of the bus before it rolled over twice.
The bus was bound for Kolkata, formerly known as Calcutta, and was completing a tour of Hindu religious temples in the Bengal region, the report said.
Swim Week Miami Beach 2014 [PHOTOS]