A second explosion reported in Afghanistan — and there are US casualties: report

Politico's Pentagon reporter, Lara Seligman tweeted that another explosion has been reported at the Afghanistan airport where Americans and refugees are attempting to flee the country.

While there is no official confirmation from officials, she said that three sources have confirmed that there are American casualties and that the U.S. forces returned fire. The Pentagon was expected to hold a briefing at 10:30 a.m. EST, but that has since been delayed.

"We can confirm that the explosion near the Abbey Gate of the Kabul airport has resulted in an unknown number of casualties. We will continue to update," Pentagon press secretary John Kirby tweeted.