Mexico City, September 1 (EFE-RHC) -- At least 500 industrial workers were evacuated following an explosion in a gas pipeline in San Miguel Xoxtla, a town in the central Mexican state of Puebla, but no one was injured in the blast, emergency management officials said.

A pipeline belonging to state-owned oil giant Petroleos Mexicanos, or Pemex, exploded Saturday morning, Puebla state emergency management office director Jesus Morales said. The pipeline runs along the side of a highway that connects the town to Mexico City.

Army troops and police brought the fire under control and investigators are trying to determine what caused the explosion.

Companies operating in the San Miguel Xoxtla industrial zone were evacuated and the blaze forced the closing of the Puebla-Mexico City highway for about two hours, officials said.

Theft of fuel from Pemex pipelines, known in Mexico as "milking," is common, with both individuals and gangs involved in the illegal activity. A total of 2,523 fuel theft cases were registered in 2013, Pemex said.

Tamaulipas, Sinaloa, Jalisco, Sonora, Veracruz and Puebla are the states with the most reported cases of fuel theft via illegal pipeline taps.