The bus covered the route between the town of Tayabamba, in the La Libertad region, and the country’s capital, Lima.
The vehicle fell off the cliff while traveling on the PE-12A national highway as it passed through the municipality of Yánac.
It is understood 23 people have died, local media reports.
Local governement had previously called for repairs on the road’s “terrible conditions”.
Town mayor, Carlos Pinedo, urged authorities to improve this section of the road.
“This road is in terrible conditions and as a result of that, of those failures that are all hollow, now are the consequences,” he said.
“We should not wait for more deaths.”
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