Iran fired at least a dozen missiles early Wednesday, local time, at U.S. military bases in Iraq, in an apparent retaliation against the killing of Iranian Maj. Gen. Qassem Soleimani, a top general who led Iran’s Islamic Revolutionary Guard Corps.

Read: Who was Qassem Soleimani, and why is his death a major development in U.S.-Middle East relations?[1]

The Wall Street Journal reported that two military bases, one at Erbil in northern Iraq and another at Al Asad in western Iraq, were struck, but according to early reports, there have been no casualties indicated yet.

The rapid-fire missile attack may mark the first time that the Islamic Republic has directly struck U.S. military or other state targets and acknowledged doing so, according to the Los Angeles Times[2].

Iranian Foreign Minister Javad Zarif via Twitter had this to say: “Iran took & concluded proportionate measures in self-defense under Article 51 of U.N. Charter [3]targeting base from which cowardly armed attack against our citizens & senior officials were launched.”

“This would be the first time since Iran-Iraq War that Tehran has directly launched missiles against a state, rather than at non-state or sub-state entities,” wrote Michael Elleman, a senior fellow of nonproliferation and nuclear policy at the International Institute for Strategic Studies, London-based think tank in a Tuesday tweet.

“We do not seek escalation or war, but will defend ourselves against any aggression,” Zarif wrote.

It’s unclear if the statement will, indeed, conclude rising tensions between Tehran and Washington, as the Pentagon said that damage was still being assessed at the bases. However, military experts said that, if nothing else, the attack may reveal improvements in Iran’s ballistic-missile systems.

A Washington Post article [4]described improvements in Iranian ballistic prowess as making a “quantum change,” citing precise mid-September attacks [5]by apparent Iranian forces on Saudi Arabian oil facilities as one key sign of its advancements.

“What we’ve seen in Iran in the past few years is a change from missiles that were mainly political or psychological tools to actual battlefield weapons. This is a quantum change,” the Post quoted Fabian Hinz, who works at the Middlebury Institute of International Studies in Monte­rey, Calif, as saying.

The Post continued:

The result is a line of short- and medium-range missiles that can deliver warheads with an accuracy range in the tens of meters, a Defense Department intelligence official said. The official spoke on the condition of anonymity to discuss sensitive assessments of Iran’s military capability.

On Wednesday, Reuters, citing sources familiar with intelligence assessments[6], fed speculation that Iran deliberately sought to avoid U.S. military casualties in its missile strikes in Iraq, which some believe provides further evidence of the preciseness of Tehran’s missile systems....

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