after about 30 minutes, the witness heard van wert's husband shouting. a boat came to help, but she died on the beach. she's the second person recently killed by a shark in the bahamas. >> we turn now to the southern border. our team finding more desperate scenes amid a new surge in migrant crossings overwhelming border authorities. a policy change in mexico now threatens to make matters even worse. abc's lionel moise explains. >> this morning, new concerns on the southern border as more migrants risk their lives to enter the us. a in texas, this near drowning in the rio grande. a border agent helping save the guatemalan national struggling in the water in california, tent cities are popping up in the small town of jacumba hot springs. migrants are climbing through a small opening where the border wall ends. arriving at this camp with no shelter, beds or food, some using wood and trash to make shelters. hundreds sharing just two portable toilets. >> this is ridiculous that we are doing this for the for the government, the community helping to provide ess