Cesilia was last seen riding the subway on her way home from school at the 149th Street station between 3:00pm and 4:00pm on October 6, 1976. A witness came forward several days after Cesilia initially vanished stating that she saw Cesilia on that day on the corner of 163rd Street and Southern Boulevard with a resident of the Bronx named Anthony "Rudy" Flores. Flores was holding Cesilia by her arm and she appeared frightened of him. Flores claimed that he was not with Cesilia the day she vanished. She was wearing a parochial school uniform, a light gray jacket, a gray plain skirt, and a white blouse. She has a scar on her left forearm.