MEXICO CITY - As many as 11 forest fires have spread through 2,500 hectares of land in Mexico's north central state of San Luis Potosi, forcing at least 400 people to leave their homes, local authorities said Sunday.

Jose Guadalupe Torres Armenta, the secretary of the state cabinet, said they would ask the federal government to declare a state of emergency, as five most affected municipalities were in Mexico's heavily forested Huasteca region.

San Luis Potosi has also asked the neighboring states for help to deal with the disaster, considered the worst in the history of the state.

More than 500 professional and volunteer firefighters have been trying to contain the blaze, digging more than 450 km firebreaks.