NORTH SAN DIEGO COUNTY (CBSLA) — Three were people killed and 18 injured Saturday after a charter bus rolled over on the southbound 15 freeway south of the 76 freeway. Eighteen of the victims were transported to the hospital.

Though there were minors involved in the crash, authorities said none of the deceased were minors.

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For unknown reasons, the bus driver lost control while travelling southbound on the freeway and tumbled down the embankment. It was raining at the time of the incident, according to authorities.

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“Given the weather conditions and the slope of the terrain, this simply adds to the difficulty of such incidents,” said San Diego fire chief Stephen Abbott. He also said that authorities believe all the people on board the bus have been accounted for.

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Authorities have not confirmed who owns the bus, only stating that it is a charter bus.