http://www.fas.org/man/dod-101/ops/war/iran-iraq.htmIn March 1984, the tanker war entered its second phase when Iraq initiated sustained naval operations in its self-declared 1,126-kilometer maritime exclusion zone, extending from the mouth of the Shatt al Arab to Iran's port of Bushehr. In 1981 Baghdad had attacked Iranian ports and oil complexes as well as neutral tankers and ships sailing to and from Iran; in 1984 Iraq expanded the so-called tanker war by using French Super-Etendard combat aircraft armed with Exocet missiles.
In March 1984 an Iraqi Super Etendard fired an Exocet missile at a Greek tanker south of Khark Island. Until the March assault, Iran had not intentionally attacked civilian ships in the Gulf.
Neutral merchant ships became favorite targets, and the long-range Super-Etendards flew sorties farther south. Seventy-one merchant ships were attacked in 1984 alone, compared with forty-eight in the first three years of the war. Iraq's motives in increasing the tempo included a desire to break the stalemate, presumably by cutting off Iran's oil exports and by thus forcing Tehran to the negotiating table. Repeated Iraqi efforts failed to put Iran's main oil exporting terminal at Khark Island out of commission, however.
The new wave of Iraqi assaults, however, led Iran to reciprocate. In April 1984, Tehran launched its first attack against civilian commercial shipping by shelling an Indian freighter.
Iran attacked a Kuwaiti oil tanker near Bahrain on May 13 and then a Saudi tanker in Saudi waters five days later, making it clear that if Iraq continued to interfere with Iran's shipping, no Gulf state would be safe. Most observers considered that Iraqi attacks, however, outnumbered Iranian assaults by three to one. Iran's retaliatory attacks were largely ineffective because a limited number of aircraft equipped with long-range antiship missiles and ships with long-range surface-to-surface missiles were deployed. Moreover, despite repeated Iranian threats to close the Strait of Hormuz, Iran itself depended on the sea-lanes for vital oil exports.