Iran's attempt to test launch a missile from one of its midget submarines has failed, Fox News reported two US officials as saying on 3 May.
The officials said the test was carried out in the Strait of Hormuz using a Yono-class submarine: a North Korean design that is produced in Iran as the Ghadir. It was not stated when the failed test took place.
There were reports in February that Iran had test-fired a submarine-launched cruise missile called the Nasir.
When images of the Nasir were released for the first time in April, it appeared to be based on the Nasr anti-ship missile, the Iranian version of the Chinese C-704, that has an air-breathing engine rather than a solid-fuel motor as well as a booster that together would give it a significantly longer range than the 38 km listed for the Chinese missile.
A consignment of Nasirs was then handed over to the Islamic Revolution Guards Corps Navy (IRGCN) in a ceremony on 22 April.
While the Iranian media made no mention of the Nasir being a submarine-launched missile during its coverage of the handover ceremony, with the addition of folding control fins it could potentially be encapsulated so that it could be launched from the 533 mm torpedo tubes on both Iran's Ghadir and 'Kilo'-class attack submarines.
There has been speculation - but no evidence - that Iran received 3M-54 Club submarine-launched anti-ship missiles from Russia for the three 'Kilos' that were delivered in the 1990s.
Meanwhile, there have also been indications that Iran is working on its own submarine-launched missile. Most notably, in February 2015, Iranian television showed footage of a sub-surface launch of what IRGCN commander Rear Admiral Ali Fadavi described as a "very special weapon".
That test appeared to be a failure as the footage showed the missile producing a double exhaust plume, suggesting its launch capsule was not discarded correctly or its motor was venting from the side of its airframe.
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