The Battalion Search and Rescue Organization, based in Ajo, Arizona, conducts regular expeditions into the southern Arizona desert to locate and identify the remains of migrants who died during border crossings. According to the Pima County Medical Examiner, over 150 migrants died in southern Arizona in the previous year. During recent trips in February, the group found 10 and 8 death sites respectively, recovering bone fragments and other remains which are documented and reported to county authorities.