U.S. airstrike killed two ISIS-K members in Afghanistan, Pentagon says

A U.S. airstrike in Afghanistan killed two high-profile ISIS-K targets and injured another, Major General William Taylor said Saturday at a press conference. Officials wouldn't release the names of those killed, but described them as planners and facilitators. 

"The fact that two of these individuals are no longer walking on the face of the earth, that's a good thing," said Pentagon spokesman John Kirby.

The strike, which was announced Friday night, came after ISIS-K claimed responsibility for the Thursday attack at Kabul's airport that left at least 170 dead, including 13 U.S. service members. There are still active and dynamic threat streams against the airport in Kabul, according to Kirby, even after the strike against the ISIS-K targets. 

"We aren't thinking for a minute that what happened yesterday gets us in the clear," Kirby said. "Not a minute. But do we believe that we hit valid targets, bad guys who can do bad things and can plan bad missions? Absolutely. And do we think that that will have some impact on their ability going forward? Absolutely."

Kirby also said Saturday that "the retrograde has begun," which means the U.S. has started its withdrawal of about 5,000 troops from the Hamid Karzai International Airport in Kabul. 

On Friday, the U.S. military described the unmanned airstrike as an "over-the-horizon counterterrorism operation" against an ISIS-K planner. Captain Bill Urban, spokesman for U.S. Central Command, said it took place in the Nangarhar Province of Afghanistan. "Initial indications are that we killed the target. We know of no civilian casualties," he said.

On Friday evening, the U.S. Embassy in Kabul sent out an alert telling people to stay away from the Kabul airport due to "security threats," adding that those at four of the airport's gates should "leave immediately." 

"Because of security threats at the Kabul airport, we continue to advise U.S. citizens to avoid traveling to the airport and to avoid airport gates," the embassy wrote on its website. "U.S. citizens who are at the Abbey gate, East gate, North gate or the New Ministry of Interior gate now should leave immediately."

A defense official told CBS News on Friday that the suicide bomb that killed 13 U.S. service members is estimated to have contained 25 pounds of high explosives. An average suicide vest contains just 5 to 10 pounds. The vest also had shrapnel to increase its deadly effects.