A US warplane killed multiple Iranian-backed militiamen in Iraq after they fired a short-range ballistic missile at American and allied personnel in the country, the Pentagon said on Tuesday, according to a report in the AFP news agency.

"We can confirm an attack last night by Iran-backed militias using a close-range ballistic missile against US and coalition forces at Al-Asad Airbase, which resulted in eight injuries and some minor damage to infrastructure," Pentagon spokesman Brigadier General Pat Ryder said in a statement.

The Ain al-Asad Air Base is located in the desert of Iraq's Western Anbar province and hosts forces of the US-led coalition fighting the Islamic State (ISIS) group in Iraq.

"Immediately following the attack, a US military AC-130 aircraft in the area conducted a self-defense strike against an Iranian-backed militia vehicle and a number of Iranian-backed militia personnel involved in this attack. This self-defense strike resulted in several enemy KIA (killed in action)," Ryder said, as quoted by AFP.

This marks the first time the United States has announced a strike on Iranian proxy forces in Iraq. It previously has hit Tehran-linked sites in Syria on three occasions in response to attacks on US troops in that country.

The surge in attacks on American troops is linked to the latest war between Israel and Hamas, which began on October 7 when Hamas carried out a cross-border attack from Gaza.

Last week, the Pentagon said that there have been 56 attacks on US troops in Iraq and Syria since October 17, with 59 US personnel getting injured with either traumatic brain injury (TBI) or non-serious injuries.

On Tuesday, deputy Pentagon Press Secretary Sabrina Singh updated those numbers and told reporters in Washington that US forces "have been attacked approximately 66 times since October 17 -- 32 separate times in Iraq and 34 separate times in Syria."