During the closing stages of the Iran-Iraq War the United States Navy began conducting operations in the Persian Gulf to protect US flagged ships from attack by Iranian naval forces. A secret plan was put in place and dubbed Operation Prime Chance. Navy SEAL Teams 1 and 2 along with several Special Boat Units and Navy EOD teams were employed on mobile command barges and transported by helicopters from the Army’s 160th Special Operations Aviation Regiment. Over the course of the operation SEALs conducted VBSS missions to counter Iranian mine laying boats. The only loss of life occurred during the take down of the Iran Ajr. Evidence gathered on the Iran Ajr by SEALs and EOD techs later allowed the US Navy to trace the mines that struck the USS Samuel B. Roberts. This chain of events lead to Operation Praying Mantis, the largest US Naval surface engagement since the Second World War.