Two advocacy groups working along the U.S.-Mexico border are accusing Customs and Border Protection of human rights abuses and violating international law over the agency’s practice of detaining immigrants and asylum seekers in open-air sites, where they’re exposed to extreme weather and other dangerous conditions. The Southern Border Communities Coalition and Center for Human Rights and Constitutional Law have warned the Trump administration may expand its use of open-air detention in New Mexico, Arizona and California by having the U.S. military seize control of a buffer zone along a sprawling stretch of the southern border. The groups are urging the United Nations Human Rights Council to review the practice.