Iran claimed it used a U.S.-made Stinger missile to shoot down an Iraqi jet fighter over the Persian Gulf. An Iranian communique said a search was under way for the pilot, who it said parachuted into the northern gulf near the Faw Peninsula. Iraq's military command confirmed the missile attack but denied that the Soviet-built MIG had been hit. Iran is believed to have acquired the Stinger missiles from Afghan guerrillas. Iraq also said that its warplanes rocketed another Iranian oil tanker in the gulf, the second such attack in four days. Shipping sources said the latest attack damaged the Alamoot, a 317,824-ton ship owned by the Iranian national oil company.