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KABUL, Afghanistan (NewsNation Now) — At least two explosions rocked the area around Kabul’s airport amid a huge and chaotic evacuation effort from Afghanistan Thursday, the Pentagon said.

Civilians and U.S. service members are among the casualties of what was described as a “complex attack” by the Pentagon.

Pentagon spokesman John Kirby said one blast occurred near the airport’s Abbey Gate and the other close to the nearby Baron Hotel. Two U.S. officials said at least one of the explosions appeared to be from a suicide bombing.

There is no official death count, but a Taliban official said at least 13 people were killed in the blast, including children, and many Taliban guards were wounded.

A U.S. official told Reuters as many as three U.S. service members were among those hurt, and that U.S. casualty numbers were expected to increase, according to initial information. At least one of the U.S. personnel was seriously hurt, an official said. Russian officials said at least two were dead and 15 were injured.

A massive airlift of foreign nationals and their families as well as some Afghans has been under way since the day before Taliban forces captured Kabul on Aug. 15, capping a swift advance across the country as U.S. and allied troops withdrew.

Over the last week, the airport has been the scene of some of the most searing images of the chaotic end of America’s longest war and the Taliban’s takeover, as flight after flight took off carrying those who fear a return to the militants’ brutal rule.

The United States has been racing to carry out the airlift before its military is set to fully withdraw from the country on Aug. 31.

This story is developing. Refresh for updates.

Reuters and the Associated Press contributed to this report.