Determined to Flee China, Thousands Take a Long, Dangerous Route to the Southern U.S. Border

On a crowded speedboat making a night crossing in rough waters off Colombia in January, Daniel Huang, a former Shanghai fitness trainer, began to regret his decision to try to enter the U.S. via Latin America.

He was soaked through by the crashing waves and he feared the boat would tip over. On his cellphone, he said he typed up a farewell note to his father to send if it seemed he wouldn’t make it to the shore on the Panamanian side, where he would start an arduous jungle trek…