The accident occurred on Sunday because of a technical fault, when the bus was traveling from Oaxaca to Mexico City, Mexican press reported, citing local law enforcement agencies. At least 50 passengers were in the bus, mostly illegal migrants from Venezuela and Colombia, the report said.
All those injured were reportedly transferred to hospitals.
Representatives of the road authorities, police and the National Institute of Migration have arrived at the site to investigate the cause of the accident, the new outlet added.