Mexican officials are searching for answers after an explosion at the Mexico City headquarters of the state-run Pemex oil company killed at least 32 people. More than 100 others were injured.
The blast late Thursday shattered the lower floors of the company's more than 50-story tower in the capital. Helicopters, firefighters and emergency technicians were quickly on the scene searching for survivors. Some of the injured were being rolled away on gurneys, while others were pushed out on rolling office chairs.
There is no word yet on what caused the blast, but officials say equipment problems in the basement may have been responsible.
Mexican President Enrique Pena Nieto visited the site of the blast late Thursday. He offered his condolences to the families of the victims, and said he has ordered an investigation.
This is not the first deadly accident at a Pemex facility.
In September, a huge explosion at a Pemex plant near the city of Reynosa killed 30 people.
In 2010, a Pemex oil pipeline exploded in the central town of San Martin Texmelucan, killing 29.