MEXICO CITY, Feb. 1 (UPI) -- Mexican Interior Minister Miguel Angel Osorio Chong said an investigation was under way to determine what caused a deadly explosion at Pemex offices.
At least 25 people died and more than 100 were injured when an explosion Thursday rocked the headquarters of state-owned oil company Petroleos Mexicanos in Mexico City.
"The authorities are using all resources to investigate and understand the causes of this incident," Chong was quoted by Bloomberg News as saying.
The Mexican government said Friday it hasn't confirmed a cause of the explosion.
Mexican President Enrique Pena Nieto, in office since December, vowed to revitalize the national energy sector. The U.S. Energy Department ranks Mexico No. 8 in the world in terms of oil production. Its position as a net exporter, however, has dropped as has oil production levels.
In early 2012, U.S. and Mexican officials signed an agreement on the exploration of oil and natural gas along a shared maritime border in the Gulf of Mexico.