MEXICO CITY — An explosion ripped through the high-rise headquarters of Mexico’s state oil company Friday, killing at least 14 people, according to a government minister, and injuring more than 100.

The explosion shook the iconic 54-story headquarters of Petroleos Mexicanos, the second tallest building in the capital, at 3:55 p.m. local time, the end of the Mexican lunch break when hundreds of people would have been moving about the complex. As darkness fell, search teams were pulling people from the complex. Presidential spokesman David Lopez said employees remained trapped inside.

Pemex, said on its Twitter account that the explosion hit a smaller building adjacent to the main tower, causing damage to the first and second floors and leading to the evacuation of the complex.

The cause was not immediately known.

“It was a big explosion. Then we were amid rubble,” Pemex employee Cristian Obele told the Milenio television network. “I’ve never lived through something like this.”

Interior Secretary Miguel Osorio Chong told Foro TV that 13 people had died at the site, another perished at a hospital, and “more than 80 persons are injured up to this point.”

“The priority at this time is to attend to the injured and ensure the physical safety of those who work there,” President Enrique Pena Nieto said on his Twitter account.

Thirty people remained missing, Foro TV said. Rescue teams using sniffer dogs took part in a search effort. Shattered glass littered streets surrounding the complex, which is located in the Anzures district near central Mexico City. Sirens from ambulances wailed throughout the streets surrounding the complex and helicopters hovered overhead.

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