Humanitarian aid groups are accusing Malta of violating international law after facilitating the forced return of hundreds of asylum seekers to Libya, where they were then imprisoned under horrific conditions. The group of some 500 migrants, including dozens of children and pregnant people, were on a boat to Europe when their ship went adrift last week, leaving them stranded in the Mediterranean as the boat started filling up with water. The asylum seekers called a humanitarian hotline for help. Maltese authorities responsible for search and rescue missions in the region never arrived. The group was instead captured at sea by what’s believed to be a Libyan militia group, and taken to a prison in Benghazi. Human rights groups have long denounced the torture, forced disappearances and other dangers faced by asylum seekers in Libya, which U.N. experts say amount to crimes against humanity.