Cuban rafters rescued…in Guatemala

Central American news outlet is reporting that 23 Cuban rafters were rescued near the northeast of that country. It’s reported that there were twenty men and three women ranging in age from 19-50. They were rescued when their raft was damaged after encountering inclement weather. Unfortunately the rafters are being detained by the Guatemalan immigration authorities and “together with Cuban diplomats they will determine the legal process to undertake.” Why would a sovereign nation allow foreign diplomats from the country these people were trying to escape determine what legal process to take about citizens?