• There was an explosion outside a gate at Kabul airport amid ongoing evacuations.
  • The Pentagon confirmed early reports on Thursday but declined to provide any details.
  • It is unclear how many people may have been injured or killed.
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There has been an explosion outside Hamid Karzai International Airport in Kabul, where efforts to evacuate people out of Afghanistan are ongoing, the Pentagon said on Thursday.

"We can confirm an explosion outside Kabul airport," Pentagon press secretary John Kirby said in a statement. "Casualties are unclear at this time. We will provide additional details when we can."

US officials told CNN that there were Afghans injured, but there is currently no information available about potential US casualties. People have been crowding outside the gates for days.

A US official told Fox News reporter Jennifer Griffin that a suicide bomber launched a "complex" suicide-bombing with an improvised explosive device and that there was a firefight outside Abbey Gate.

Politico reporter Lara Seligman, citing two sources, also said the cause was a suicide bomber.

Over the past few days, the US has expressed concerns about possible terrorist activity around the airport. There have been specific concerns about ISIS-K, an ISIS affiliate in Afghanistan.

US President Joe Biden warned of this threat on Tuesday, saying that "every day we're on the ground is another day we know that ISIS-K is seeking to target the airport and attack both US and allied forces and innocent civilians."

On Wednesday, the US Embassy in Afghanistan sent out an alert urging US citizens to avoid travelling to the airport due to "security threats" outside the gates.

A senior US official told The New York Times that the alert was in response to "specific" and "credible" threats posed by ISIS-K, a common enemy for both the US and the Taliban.

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