GUATEMALA CITY (AP) — Simple advice from a friend to stay near the door may have saved Yenifer Yulisa Cardona Tomás from the deadly fate that befell 53 other migrants when they were abandoned trapped in a sweltering semi-trailer last week on the edge of San Antonio.

Speaking by phone from her hospital bed Monday, the 20-year-old from Guatemala's capital said it was already hot on June 27 when she stepped out of the warehouse on the Texas side of the Mexico border where she had been waiting and climbed into the back of the trailer.

She said the smugglers confiscated their cellphones and covered...