Sashenka Gutierrez / EPA

Search and rescue operation in the PEMEX administrative building in Mexico City on February 01, 2013, a day after a deadly explosion. Pemex is stepping up security at oil production facilities as authorities investigate the blast, which killed at least 33 people at the state-owned company's headquarters. Read the full story.

Alfredo Estrella / AFP - Getty Images

General view inside the damaged building of state-owned Mexican oil giant Pemex in Mexico City, Mexico.

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• Deadly explosion rocks Mexico City skyscraper housing Pemex

Guillermo Gutierrez / AP

Firefighters belonging to the Tacubaya sector and workers dig for survivors after an explosion at an adjacent building to the executive tower of Mexico's state-owned oil company PEMEX, in Mexico City, Thursday Jan. 31, 2013. A large explosion occurred in the lower floors of the building.

By Kari Huus, Staff writer, NBC News

An explosion in the Mexico City skyscraper complex housing the headquarters of state oil monopoly Pemex killed 14 and injured at least 80, company and government officials said.

The explosion took place in the basement garage of the auxiliary building of the complex, next to the company's 54-floor tower located in a busy commercial and residential area, Interior Department spokesman Eduardo Sanchez told reporters.

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Alejandro Dias / Reuters

An injured person is transported on a stretcher the headquarters of state oil giant Pemex in Mexico City Jan. 31.

Yuri Cortez / AFP - Getty Images

Rescue workers head for the skyscraper.

Yuri Cortez / AFP - Getty Images

A helicopter overflies the area following a blast inside the skyscraper that houses the headquarters of state-owned Mexican oil giant Pemex.

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