Iranian plan to mine Hormuz puts US, NATO on Persian Gulf alert:

US and NATO task forces in the Persian Gulf have been placed on alert after US intelligence warned that Iran's Revolutionary Guards are preparing Iranian marine commandos to sow mines in the strategic Strait of Hormuz.

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Tehran hopes the mines in the waterway will blow up passing oil tankers and other shipping. It doesn't have to be sealed hermetically to endanger international shipping; just a few mines here and there and an explosion would be enough to deter shippers and crews from risking their vessels.

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Tehran is expected to strike back hard by sowing mines in Hormuz and in the waters opposite the oil fields and terminals of fellow Persian Gulf oil producers, including Saudi Arabia.

It would not be the first time. In 1987 and 1988, sea mines were sown in the Persian Gulf for which Iran never took responsibility. It was generally seen as Tehran's payback for US and Gulf Emirates' backing for Iraq in its long war with the Islamic Republic. A number of oil tankers and American warships were struck by mines, including the USS Samuel B. Roberts. Such disasters can be averted today by means of the sophisticated countermeasures now in US hands.