The fire department said that the bus left Guarajuba, a tourist destination in Camaçari, on its way to the city of Jacobina, also in Bahia, to cover a distance of about 360 kilometers.
Among the fatalities, there are seven men and 17 women, including one pregnant woman.
Several injured were sent to hospitals in the region, but some of them, according to the authorities, were transferred to other nearby health units.
The Bahia Federal Highway Police reported that the vehicles collided head-on (frontally). The road is still closed in the stretch where the accident occurred.
The Prefecture of Jacobina decreed a three-day official mourning and announced that it is preparing a collective vigil for the victims at the municipal sports gymnasium.
Authorities are investigating the causes of the accident.
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