Ghadir mini-submarines are built by Iran specifically for cruising the Persian Gulf. (File photo) A former US naval commander says the Iranian military has a growing fleet of mini-submarines that is particularly difficult for the US Navy to detect and track. The Iranian mini-submarines are a huge problem for us, MinnPost news website quoted retired Navy Commander Christopher Harmer, who was the director of future operations for the US Navy Fifth Fleet, stationed in Bahrain, from 2008 to 2009, as saying. They are a threat to us because they can disperse them throughout the Persian Gulf and the Arabian Sea, and its extremely difficult for us to track them, he added. Commander Harmer said that the US Navy is more accustomed to tracking large, Soviet-era nuclear-class submarines - something Iran knows well. Looking for small subs in shallow water is much more difficult, because the acoustics are so much more difficult - smaller makes less noise, he stated. Iran's Navy Commander Rear Admiral Habibollah Sayyari said on June 15 that the naval forces of the Islamic Republic will firmly counter any threat and deal with insecurity single-handedly. Over the past years, Iran has made important breakthroughs in its defense sector and attained self-sufficiency in producing important military equipment and systems. The country has repeatedly clarified that its military might is merely based on the nation's defense doctrine of deterrence and poses no threat to other countries. source: PressTV - Iran mini-subs difficult for US Navy to detect: Ex-US Navy Cmdr.