Iran says it’s deployed small submarines to act as an “invisible guardian” of the Strait of Hormuz amid a series of rejected peace deals between Tehran and the US.

The Islamic Republic has at least 16 of the Ghadir-class midget submarines, according to the International Institute for Strategic Studies. Each has a crew of fewer than 10 people and can carry either two torpedoes or two Chinese-designed C-704 anti-ship cruise missiles.