MULTAN, Pakistan (AP) — Authorities say an express train barreled into another that had derailed in Pakistan before dawn, killing at least 40 people. More than 100 were injured in Monday’s crash, and rescuers and villagers worked throughout the day to pull survivors and the dead from the crumpled cars. Later in the day, heavy machinery arrived to cut open some cars, in the hopes of rescuing several people still believed to be trapped. An official said the Millat Express train derailed in the district of Ghotki, in Sindh province, and the Sir Syed Express train hit it minutes later. It wasn’t immediately clear what caused the derailment. Train accidents are common in Pakistan, where successive governments have paid little attention to improving the poorly maintained signal system and aging tracks.