"It's going to get more complicated the way we see it, especially human rights for those who are simply looking for an opportunity to benefit their lives," said García Lara. "There have been many instances where soldiers are simply looking for migrants to prey on.

Mexican troops arrived in Ciudad Juárez and Tijuana this week and will soon patrol 18 cities near the Mexico-U.S. border.

Almost 2,000 extra troops were assigned to Tijuana, just south of California, as part of the 10,000-strong border reinforcement that President Claudia Sheinbaum pledged on Monday under the deal with Trump.