MEXICO CITY - At least 11 people died and some 70 others were injured Friday when a truck loaded with fireworks exploded during a religious parade in a village near the capital, authorities said.

The blast occurred when a malfunctioned firework landed on the truck in the middle of a march for the Jesus Tepactepec village's patron saint, the civil protection department of Tlaxcala state said.

"We saw bodies flying, then everything went black," said an eyewitness named Isidro Garcia Vazquez.

Authorities sent helicopters, ambulance vehilces and soldiers to the scene, about 110 km east of Mexico City, while Tlaxcala Governor Mariano Gonzalez Zarur declared three days of mourning.

Fireworks are commonly used in Mexican holidays and religious celebrations, but mishandling or lack of safety measures often lead to deadly accidents.