At least 700 Indians were affected by food poisoning after eating rice with eggs at a political rally in the southern Mexican state of Guerrero, health officials said.

Residents of Chilapa, located 50 kilometers (31 miles) from Chilpancingo, Guerrero’s capital, became sick and had to be hospitalized following an Institutional Revolutionary Party, or PRI, rally.

The Indians were recruited to go to a rally for PRI congressional candidate and Chilapa Mayor Sergio Dolores with promises of gifts and food, a common practice in Mexico, rally participants said.

PRI members from the Chilapa city government called residents on Tuesday morning and told them to attend a march for the candidate, rally participant Celida Nava Hernandez told Efe.

“They said we should go to the registration (of Sergio Dolores) and that they were going to give us provisions and food, so we went with our children,” Nava Hernandez said.

At least 700 people were treated at the hospital in Chilapa, a state Health Secretariat spokesman said.

Residents said they felt ill after going home and experienced vomiting, dizziness and diarrhea.

Health officials did not provide any figures on the number of children who became ill, but residents said at least 70 were sickened by the food.

All residents affected by food poisoning are in good condition, the secretariat said.

Politicians in Mexico regularly provide food and other enticements to get people to attend campaign rallies and to get them to vote for their party.