Pentagon officials confirmed the deaths of at least 12 U.S. service members in suicide bombings outside of Hamid Karzai International Airport in Kabul, Afghanistan, on Thursday.

“We can confirm that a number of U.S. service members were killed in today’s complex attack at Kabul airport. A number of others are being treated for wounds. We also know that a number of Afghans fell victim to this heinous attack,” the Pentagon said in a statement. At a later briefing, officials said at least 12 had died but the situation was fluid, suggesting the death toll among American troops may increase.

“We know that 12 U.S. service members have been killed in the attack and 15 more have been injured. A number of Afghan civilians were injured,” Marine Gen. Kenneth McKenzie, the head of the Pentagon’s Central Command, which runs Afghanistan operations, told reporters. The Pentagon added to that number another 15 service members injured.

The Islamic State (ISIS) has since claimed responsibility for the devastating attack, following the Pentagon’s assertions that it had “assessed” the terrorists to be affiliated with the Islamic State Khorasan Province (ISIS-K), its Afghan/Pakistani affiliate.

McKenzie said at the press briefing that the Taliban, itself a Sunni jihadist terrorist organization, is providing security at the Kabul airport while the U.S. military shares intelligence with them. He did not offer a clear answer to how suicide bombers appeared to penetrate the Taliban’s defenses. Gen. McKenzie said he did not know if the Taliban intentionally let the Islamic State suicide bombers get through and conduct the deadly bombings.

The jihadist attack left at least 60 people dead and another 150 people wounded, according to reports.

Thousands of American citizens and allies remain stranded in Afghanistan, but the Biden administration has not indicated it would extend America’s military presence in the country beyond August 31. Biden announced he would keep troops in the country through September 11, then modified the date to August 31, in April, breaking an agreement predecessor Donald Trump made with the Taliban to leave by May 1. The Taliban made unprecedented territorial gains between April and July, claiming they were now untethered by their commitments in the deal, and took over Kabul on August 15.

The Kabul Airport bombings make for the largest one-day loss of U.S. soldiers’ lives in Afghanistan since August 6, 2011 – during the Obama administration, while Joe Biden was vice president – when a CH-47 Chinook helicopter carrying 30 American servicemen, including 22 Navy SEALs, was shot down by Taliban fighters with a rocket-propelled grenade.

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