The accident happened on northbound Highway 99 in Tulare just before midnight. Authorities say the semi-truck came to a sudden stop and was rear-ended by the Fronteras Del Norte tour bus.
Fifteen of the 35 people on the bus suffered minor injuries and were transported to local hospitals. Seventeen others reported minor injuries but refused medical treatment, police said.
The driver of the semi-truck was hospitalized for minor injuries, and the bus driver also suffered minor injuries but said he would seek his own medical aid, according to a police report. Those who were hospitalized have all been released.
The bus was headed to Washington state. The crash remains under investigation.