Tehran, Sept. 7 -- Iran said it targeted three oil tankers using an unauthorized route through the Strait of Hormuz, as well as a number of US-linked ships, in retaliation for American attacks on Iranian tankers over the weekend. The Islamic Revolutionary Guard Corps Navy gave no further details about the incidents, nor did its Telegram post late Saturday specify whether the vessels were hit. The IRGC later said it also attacked a US naval drone and an American military unmanned surface vessel attempting to enter the strait. There was no immediate independent corroboration of further attacks around the waterway, a chokepoint for global energy shipments whose fate has become key to any US-Iran peace agreement. The IRGC announcement came after the US military said it struck three Iranian crude tankers, destroying one, in response to the IRGC targeting two US Navy warships with ballistic missiles. The latest flurry of tit-for-tat attacks suggest little immediate prospect of an end to the war the US and Israel launched on the Islamic Republic more than six months ago. Observable traffic through the Strait of Hormuz, which links the Persian Gulf to the Gulf of Oman, remained sparse, with only one commodity vessel crossing on Saturday, Kpler data show. The speaker of Iran's parliament and lead negotiator in previous ceasefire talks, Mohammad Bagher Ghalibaf, on Sunday warned the era of "proportionate responses" was over....