In Mexico City, at least 25 people are dead and 101 wounded after an explosion at the headquarters of Mexico’s state-owned oil firm, Pemex. Dozens were reportedly trapped after the explosion, with authorities warning the number of casualties could rise. The blast occurred in the basement of a building in an office complex that also houses one of the city’s tallest skyscrapers, Pemex tower. The cause of the blast is still unknown. Pemex initially said it had evacuated the building because of an electrical problem, but it later tweeted that the attorney general’s office was investigating the blast. Last September an explosion at a Pemex facility in northern Mexico killed 30 people.