MEXICO CITY (AP) – An explosion at the main headquarters of Mexico’s state-owned oil company in the capital killed 14 people and injured 100 on Thursday as it heavily damaged three floors of a building, sending hundreds into the streets and a large plume of smoke over the skyline.

Another 30 people remained trapped in the debris late Thursday, according to the Interior Ministry, as teams of military with rescue dogs showed up to extract the victims. The blast occurred in the basement of an administrative building next to the iconic, 51-story tower of Petroleos Mexicanos, or Pemex, one of the tallest buildings in Mexico City.

“It was an explosion, a shock, the lights went out and suddenly there was a lot of debris,” employee Cristian Obele told Milenio television, adding that he had been injured in the leg. “Co-workers helped us get out of the building.”