CNN, Aug. 27: At least two suicide bombs went off Thursday at a busy gathering area outside the international airport in Kabul, Afghanistan, a Pentagon spokesman said. Afghan civilians and US service members were killed in the attack.

The Hamid Karzai International Airport has been the epicentre of a massive evacuation operation in the days since the Taliban seized control of Afghanistan. Over the past two weeks, tens of thousands of people have been evacuated from the airport by the US military and NATO allies.

US officials believe ISIS-K, the ISIS branch that rivals the Taliban in Afghanistan, was likely behind Thursday's attack. President Joe Biden revealed that he has ordered military commanders "to develop operational plans to strike ISIS-K assets, leadership and facilities."

"We will respond with force and precision in our time, in a place we choose in a manner of our choosing," he said, declining to give specifics on timing.

People who were injured in Thursday's bomb attacks are visited by family members at a hospital in Kabul. Marcus Yam/Los Angeles Times/Shutterstock

Smoke rises from an explosion outside the airport on Thursday. Wali Sabawoon/AP

An injured person waits to be transported near the airport. Jim Huylebroek/The New York Times/Redux

Afghan refugees are gathered outside the Baron Hotel in Kabul as the British military secures the perimeter on Thursday. Marcus Yam/Los Angeles Times/Shutterstock

A bloodied shield stands outside the entrance of a Kabul hospital after Thursday's bomb attacks. Jim Huylebroek/The New York Times

An injured man is seen outside a hospital after Thursday's attacks. Victor J. Blue/The New York Times/Redux

A bloodied gurney is seen at a Kabul hospital on Thursday. Victor J. Blue/The New York Times/Redux

Taliban members guard a road near the airport after a bombing on Thursday. Jim Huylebroek/The New York Times/Redux

An injured patient waits to be transported to another floor at the Wazir Akbar Khan Hospital in Kabul. Marcus Yam/Los Angeles Times/Shutterstock

A person injured in a bomb blast is carried outside a Kabul hospital on Thursday. Victor J. Blue/The New York Times/Redux

British soldiers secure the perimeter outside the Baron Hotel in Kabul on Thursday. Marcus Yam/Los Angeles Times/Shutterstock

A person is wheeled on a stretcher outside a hospital on Thursday. Marcus Yam/Los Angeles Times/Shutterstock

Injured women arrive at a hospital for treatment on Thursday. Wakil Kohsar/AFP/Getty Images

An ambulance rushes to the site of an explosion near the airport on Thursday.Jim Huylebroek/The New York Times/Redux

Volunteers and medical staff unload bodies at a hospital after the bomb blasts. Wakil Kohsar/AFP/Getty Images

An injured person arrives on a stretcher at a Kabul hospital on Thursday. Jim Huylebroek/The New York Times/Redux

A man receives medical attention outside a Kabul hospital on Thursday. Victor J. Blue/The New York Times/Redux

People are sent away from the scene of a bomb blast outside the airport on Thursday. Jim Huylebroek/The New York Times/Redux