Iran is going to launch a Chinese-built submarine into the Caspian Sea by the middle of 2015, Azerbaijan's APA news agency has reported, citing military sources. APA said the sub is now being built at Iran's Anzali shipyard "with the participation of a Chinese company" and will be 50 meters long.
The sub will reportedly be part of the Islamic Revolution Guards Corps navy (separate from Iran's regular navy) which Iran announced last year would be taking more responsibility for the Caspian, a suggestion that Tehran was elevating the importance of Caspian security.
Those are all the details APA gives, and there is ample reason for skepticism. Iran usually inflates its own military capacity, so it's not clear why they would have been scooped by the Azerbaijani media. Secondly, It's not the most reliable source; APA recently reported that Azerbaijan's Baku Shipyard would be building the country's first warship, but shipyard officials told The Bug Pit that they had no plans to build any warships.
Earlier this year Iran announced that it would soon launch its first destroyer into the Caspian. This despite the fact that Iran held a televised ceremony last year to celebrate the launching of the first destroyer in the Caspian. So it's hard to say what's going on with Iran's Caspian fleet. But they may, or may not, be getting a Chinese-built submarine next year.
UPDATE: Thanks to reader Doug Pologe for pointing out that Jane's had noticed satellite images of a submarine under constriction on the Caspian last fall. It was "under construction at the Bandar Anzali Naval Base on the Caspian Sea on 17 September. It is partially shrouded by scaffolding, but is approximately 48 m long and 6 m wide," Jane's reported. "The construction of one of the boats at Bandar Anzali is particularly significant as this will be the first submarine to be launched on the Caspian. Iran has yet to come to a boundary agreement with the other littoral states and has been expanding its naval presence on the sea in recent years, most notably by building a Mowj (Jamaran)-class frigate at Bandar Anzali."