In the midst of ongoing evacuations, there was an explosion at Kabul's airport gate.
Although the Pentagon confirmed some early reports, it declined to give any further details.
It is not clear how many people were injured or killed.
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According to the Pentagon, there was an explosion at Hamid Karzai International Airport, Kabul. There are currently efforts to evacuate Afghans.
John Kirby, Pentagon press secretary, stated that an explosion was confirmed outside Kabul Airport. "Casualties remain unclear at the moment. We will update you with additional information as soon as we can.
The explosion occurred just outside the gate where thousands of people throng daily to try to get in to the airport to leave Afghanistan.
CNN reported that several US officials claimed that Afghans had been injured. Reuters and Fox News both report that US military personnel were also injured in the incident.
Fox News reporter Jennifer Griffin was told by a US official that a suicide bomber had launched a complex attack using an improvised explosive weapon and that there was a fight outside Abbey Gate.
Lara Seligman, Politico reporter, said that the suicide bomber was also responsible. Three US officials stated to CNN reporters that it "appears" to be a suicide attack. Similar reports also stated the same.
In the last few days, US officials expressed grave concern about terrorist activity at the airport. Concerns have been raised about ISIS-K in Afghanistan, which is an affiliate of ISIS.
On Tuesday, President Joe Biden warned about this threat by saying that "everyday we're on ground is another day that we know that ISISK is trying to target the airport in an attack on both the US and allied forces as well as innocent civilians."
The US Embassy in Afghanistan issued a security alert Wednesday, urging citizens not to travel to the airport because of "security threats outside the gates".
According to a senior US official, the alert was issued in response to ISIS-K's "specific" threat. This is a common enemy of both the US as well as the Taliban. At this point, it is unclear if ISISK was involved in Thursday’s incident.
This is a breaking story that will be updated as additional information becomes available.