On 20 June 2019, Iran's Islamic Revolutionary Guard Corps shot down an RQ-4A drone in the Strait of Hormuz near Kuhmobarak in Iran's southern province of Hormozgan. Iran claimed it was in their airspace, while the US claimed it was in international airspace. An anonymous U.S. official initially claimed it was an MQ-4C Triton drone, but the U.S. Central Command later confirmed it was a (BAMS-D) a prototype version of the RQ-4A drone, developed during the development of the MQ-4C. Four in total, of these prototype aircraft were built and they had been assigned to the Navy's Broad Area Maritime Surveillance (BAMS) program.