The bus was carrying 90 passengers when it fell into the ravine from a highway, about 64 km from Guatemala City, was destroyed, reported Xinhua citing fire department.
"We have counted 35 dead and we have not finished rescue work at the site," said fire department spokesperson Cecilio Chacaj, adding the bus was meant to carry 60 people.
Though the exact cause of the accident was yet to be ascertained, initial investigation suggested brake failure could have led to the tragedy, authorities said.
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