Attacks on American troops stationed in Iraq and Syria in recent days, attributed to Iran-backed militia forces, came as the nuclear talks in Vienna were making some progress.
US officials in recent weeks had warned that they expected more attacks against US forces in Iraq and Syria, in part because of the second anniversary of the killing of top Iranian general Qasem Soleimani.
Soleimani who was Iran’s top military and intelligence operator in the Middle East, organizing anti-American and anti-Israeli militant groups, was killed by a targeted US drone strike on January 3, 2020, directly ordered by former US president Donald Trump.
Two explosive-laden drones were shot down on Tuesday by Iraq's air defenses as they approached the Ain al-Asad air base, which hosts US forces, west of Baghdad, an official of the US-led international military coalition said.
A similar attack was foiled on Monday, when Iraqi air defenses downed two drones as they approached a base hosting US forces near Baghdad's international airport.
Separately, another coalition official told Reuters that the coalition had carried out strikes against an "imminent threat" after they saw several rocket launch sites near the Green Village in Syria.
While this official did not say which country in the coalition carried out the strikes or who was responsible for the launch sites, Iranian-backed militia groups have occasionally targeted US forces in both Iraq and Syria.
In Washington, Pentagon spokesman John Kirby refused to say that the latest attacks were tied to Iran, but said they follow a pattern of attacks that were carried out by Iranian networks in the past.
"I'm not in a position now to get into specific attribution. That said, we continue to see threats against our forces in Iraq and Syria by militia groups that are backed by Iran," Kirby told reporters.
He also said the coalition strikes in Syria were not carried out by aircraft but did not provide more details on the threat.
The attacks came as nuclear talks continued with Iran in Vienna that seem to be making some progress. Critics of the talks to restore the 2015 nuclear agreement known as JCPOA say that even if negotiations prove successful they would not impact Iran's agressive behavior in the region and its network of militant proxies.
Iranian threats of revenge and retribution increased in the past one week as Soleimani’s death anniversary approached. Both Iran’s Supreme Leader Ali Khamenei and hardliner president Ebrahim Raisi warned that those involved in the Soleimani’s killing must be held responsible.
"If Trump and (former Secretary of State Mike) Pompeo are not tried in a fair court for the criminal act of assassinating General Soleimani, Muslims will take our martyr's revenge," Raisi said in a televised speech on Monday.
The United States is leading the international military coalition fighting Islamic State militants in Iraq and in Syria.
There are roughly 900 U.S. troops in Syria and another 2,500 in Iraq.
With reporting by Reuters