Complex sentence: Martínez gave these to one of her clients, Daniel Orlando Garza who contacted two Mexican hitmen from Matamoros, Tamaulipas, Israel Olivarez Cepeda and Heriberto Puentes Pizaña, who killed Fischer and then escaped to Mexico.
Split into simpler sentences: Martínez gave these to one of her clients, Daniel Orlando Garza. He contacted two Mexican hitmen from Matamoros, Tamaulipas, Israel Olivarez Cepeda and Heriberto Puentes Pizaña, who killed Fischer and then escaped to Mexico.