Mexico put infant vaccinations on hold after two babies died and 29 were sickened when they were given injections against tuberculosis, rotavirus and Hepatitis B, the Associated Press reported.

The incidents occurred in the rural mining community of La Pimienta, in the southern state of Chiapas, which the network described as "impoverished"; six of the surviving babies remain in serious condition.

The children had received shots administered by Mexico's national immunization program, and officials admitted they "presented adverse reactions presumably associated with the application of these vaccines," according to CNN. Nevertheless, authorities have not said what they think caused the illnesses.

The vaccinations were offered on Friday when officials came to La Pimienta, where access to medical care is difficult to come by; they announced over loudspeakers that the shots would be given to newborns, local residents told CNN México.

There are no hospitals or clinics in the area, and residents flock to a small cinder-block health center with a tin roof whenever a doctor passes through the community.

"A small selection of paracetamol and other pills sits on dusty shelves inside," CNN said of the health centers.

The Rev. Marcelo Pérez, a Roman Catholic priest, told The Associated Press that the babies had become sick within hours after receiving the injections. The children were being treated in a hospital in Simojovel, Chiapas, a facility that "doesn't have adequate personnel or equipment," according to the clergyman.

Government statistics show that in Simojovel, a municipality of about 40,000, 93 percent of inhabitants live in poverty, while 69 percent suffer from extreme poverty.

"The real problem is the terrible conditions we have ... so that when a baby comes in with convulsions, he leaves dead," Pérez said.

The priest added that he was helping the families collect all the information that could help officials discover the cause of the adverse reactions, while the federal and state governments put out a statement promising the best medical care for the babies and to stay in contact with the parents to answer all their questions.