Twenty-six dead in Mexican gas plant blaze Rescue workers could be seen carrying injured people on stretchers and into ambulances. The state monopoly said experts were investigating the cause of the fire - the third incident at a Pemex facility in a little over a month. Pemex said the fire broke out at 10.45am (1545 GMT). Workers shut off valves while firefighters spent two hours extinguishing the blaze. Guillermo Lopez, a contractor who worked with drilling teams and in maintenance areas, said the fire may have started when a tanker truck was filling a storage tank. "One of the safety valves attached to the supply hose may have failed, creating a spark that turned into two explosions," Lopez said. A pipeline and control valves were damaged by the fire and specialists are examining them, according to Pemex. The damaged plant receives gas from the Burgos basin and distributes the product to Pemex's gas and petrochemicals unit. On August 13, an explosion rocked a refinery in the Tamaulipas city of Ciudad Madero, and on the same day a fire broke out at a pipeline in the central state of Hidalgo after thieves apparently tried to steal diesel from it. No injuries were reported in either incident. The previous worst incident took place in December 2010, when an oil pipeline exploded after it was punctured by thieves in the central town of San Martin Texmelucan, leaving 29 dead, injuring more than 50 and destroying 32 homes. In October 2007, 21 Pemex workers died during a gas leak on an oil platform in the Gulf of Mexico. Most drowned when they jumped into the sea in a panic. Pemex, which accounts for 40 per cent of Mexico's government revenue, was once the world's fourth biggest oil company. But in the last 15 years it has fallen to 11th place in terms of production, with 2.55 million barrels of oil per day in 2011.