What happened

A rocket barrage struck K-1 Air Base in Iraq's Kirkuk Governorate, which hosted Operation Inherent Resolve personnel, on the evening of 27 December 2019, with at least one rocket hitting a munitions storage facility and causing a significant secondary explosion. The attack killed U.S. civilian contractor and linguist Nawres Waleed Hamid and wounded four U.S. service members and two Iraqi security personnel. The United States attributed the attack to the Iranian-backed Kata'ib Hezbollah militia based on undisclosed intelligence and intercepted communications; the group denied responsibility, and Iraqi officials later suggested the Islamic State could have been responsible given the area's Sunni-majority population and known IS activity, an attribution dispute not resolved in the reviewed reporting. The attack set off a rapid escalation chain recorded in detail elsewhere on this site: US retaliatory airstrikes killed roughly 25 Kata'ib Hezbollah fighters at facilities in Iraq and Syria, prompting militia-linked protesters to storm the US Embassy compound in Baghdad, which in turn preceded the 3 January 2020 US strike near Baghdad International Airport that killed Iranian Quds Force commander Qasem Soleimani and Popular Mobilization Forces commander Abu Mahdi al-Muhandis — the event that directly triggered Iran's 8 January ballistic-missile retaliation against Al-Asad airbase and Erbil International Airport, both recorded separately on this site.

When cited sources give different casualty, damage or spill figures for this event, they’re reported side by side above rather than merged into one number. See how confidence levels work.