The man who killed one tourist at a Mexican pyramid and wounded several others had materials in his backpack tied to a 1999 U.S. attack, a possible reference to the Columbine High School massacre. On Sunday, Julio César Jasso Ramírez checked into a hotel near one of Mexico’s most popular tourist destinations, the Teotihuacán pyramids, Mexican officials said on Tuesday. The next morning, he took an Uber to the archaeological site, climbed up th... [1576 chars]