One American is among at least 15 people killed in Poland after two trains collided head-on in the country’s southern region late Saturday night. The U.S. Consulate in Krakow said the victim’s family has been notified. It’s the country’s worst crash in more than two decades. It’s not yet known what caused the two trains, carrying about 350 passengers, to run into each other at high speed on the same track near the town of Szczechociny. At least 54 people were injured.