The Iranian Navy started the tactical phase of the military exercises underway in the international waters in the Sea of Oman and the Indian Ocean, a Navy commander said on Tuesday. Iran\'s naval forces started massive wargames, dubbed as Velayat 90, in an area stretching from the East of the Strait of Hormoz in the Persian Gulf to the Gulf of Aden on Saturday. \"After the accomplishment of the initial and expansion phases of Velayat 90, the tactical phase of the wargames was started this morning in the wargames general zone,\" Lieutenant Commander of the Iranian Navy Admiral Seyed Mahmoud Moussavi said. He added that Iranian naval forces exercised confrontation against chemical attacks of the hypothetical enemy as part of the plan to boost their defense power in modern warfare. Moussavi, who is also spokesman of the wargames, said that Iranian navy vessels embarked on fortifying the country\'s coastal waters to prevent infiltration of hypothetical enemy vessels and submarines. The commander noted that Iranian forces also conducted tests in electronic warfare field using modern home-made electronic jamming equipment to disrupt enemy radar and contact systems. Iran stages several air, land and sea wargames each year to test its newly produced weapons and equipments. Defense analysts and military observers say that Iran\'s wargames and its advancements in weapons production have proved as a deterrent factor, specially at a time of heightened threats by the US.