The Peacekeepers Book 14 Redemption

Division within the ranks of the peacekeepers threatens to tear them apart as they battle the Colombian drug cartel and a mystery enemy. Adding to their growing list of problems is the fact that the unidentified enemy is attempting to master the technology that permits them to travel submerged in their ships, which appear to be clones of those of the cartel. If ships can approach the coastal cities of America undetected, it would be all but impossible to stop them from attacking.