Fire and smoke coming from deep inside the concrete and metal remains of a collapsed 12-story condominium tower near Miami hampered rescue efforts Saturday as emergency workers raced to recover any survivors beneath the mountain of rubble.Rachel Spiegel, whose mother is among the 159 people missing, said her family is praying for a miracle. Rescuers used infrared technology, water and foam to battle the blaze, whose source was unclear, and Miami-Dade Mayor Daniella Levine Cava said the smoke has been the biggest challenge. In a news conference, the mayor described the blaze as “very deep” and said rescuers faced “incredible difficulties” because of the flames.Watch the video above to see the story of a woman praying for her mother.