MEXICO CITY - Mexico's state-owned oil company says 14 have died and 80 are injured in an office building explosion at its headquarters in the capital.

An explosion at the main headquarters of Petroleos Mexicanos, or Pemex, also damaged three floors of the building, sending hundreds into the streets and a large plume of smoke over the skyline.

There was no immediate cause given for the explosion which occurred in the basement of an administrative building next to the iconic, 52-story Pemex tower.