Spanish authorities estimate that more than 49,000 migrants crossed into the North African enclave of Ceuta from Morocco in a 24-hour period, with at least 18 dying as they tried to reach the territory. But Ceuta's president, Juan Jesús Vivas, put the number of arrivals at 60,000 and said at least 34 people had died. The migrants entered by swimming, sometimes spending hours in the water. The influx is more than half the enclave's population. The border crisis began Thursday and continued Friday, with security forces clashing with migrants on the Moroccan side of the border. Spain has since sent more than 25,000 migrants back to Morocco, according to Spanish officials.