GUADALAJARA, Mexico – Authorities said a gas leak was responsible for the explosion that killed at least 37 people at the headquarters of state oil giant Petroleos Mexicanos, or Pemex, in Mexico City last Thursday.
Attorney General Jesus Murillo told reporters late Monday that there were no signs of any explosives at the scene of the blast, Reuters reported Tuesday.
“An accumulation of gas that was combined with a spark from an electrical system in the building provoked this tragedy,” Murillo was quoted by Bloomberg as saying.
“We still need to go through a lot of steps in order to determine the precise gas that generated the explosion, its exact point of origin and the analysis of whether there are people responsible for this.”
The Associated Press said one possible source of the gas was a water-heating system.
Officials believe the gas may have leaked into a tunnel underneath the tower where it was allowed to build up for months before it was accidently ignited by maintenance workers last Thursday afternoon.
The January 31 explosion – the country’s deadliest since a mine accident in 2006 – killed 37 people and injured scores of others.
It came as Mexican President Enrique Pena Nieto prepares to submit a bill to Congress allowing greater private and foreign investment in Pemex.
If passed, it would mark the greatest overhaul of the country’s energy sector in more than seven decades.
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