Eight humanitarian volunteers who help migrants survive desert treks have been charged with federal crimes, prompting fears of an escalating crackdown by the Trump administration. The volunteers, all members of the Arizona-based group No More Deaths, appeared in court on Tuesday charged with a variety of offences including driving in a wilderness area, entering a wildlife refuge without a permit and abandoning property - the latter an apparent reference to leaving water, food and blankets on migrant trails. The charges came a week after No More Deaths, a coalition of religious and community activists, published a report accusing border patrol agents of condemning migrants to death by sabotaging water containers and other supplies. It also accused agents of harassing volunteers in the field. Hours after the report's publication one activist, Scott Warren, 35, was arrested and charged with harboring two undocumented immigrants, a felony. No More Deaths stopped short of calling it retaliation for the report but said the timing was suspicious. Warren was among the eight who appeared in court this week. No More Deaths said the charges fit a pattern of interference in efforts to save the lives of migrants who trek for days or weeks across harsh deserts which bake by day and freeze by night. The charges relate to activities in Cabeza Prieta national wildlife refuge. Some 32 sets of human remains were found there last year.