The Pentagon warned Monday of "real" and "specific" threats of new attacks at Kabul airport just hours ahead of a US deadline to complete its frenzied withdrawal from Afghanistan, which has been marred by Islamic State violence, including a volley of rocket fire.
President Joe Biden has set a deadline of Tuesday to withdraw all US forces from Afghanistan, drawing to a close his nation's longest war, which began in late 2001 in retaliation for the September 11 attacks.
The return to power a fortnight ago of the Taliban movement, which was toppled in 2001 in that US-led invasion, triggered a massive exodus of terrified people fearing a new version of their hardline Islamist rule.
Those flights, which have taken more than 122,000 people out of Kabul airport, will officially end on Tuesday when the last of the thousands of American troops pull out.
US forces are now focused chiefly on flying themselves and American diplomats out safely.
The UN Security Council adopted a resolution requiring the Taliban to honor their commitment to let people freely leave Afghanistan in the days ahead, and to grant access to the UN and other aid agencies, but did not create a "safe zone" in Kabul.
The regional Islamic State-Khorasan (IS-K) group, rivals of the Taliban, pose the biggest threat to the withdrawal, after carrying out a suicide bombing outside the airport last week that claimed more than 100 lives, including those of 13 US troops.
On Monday, they claimed to have fired six rockets at the airport. A Taliban official said the attack was intercepted by the airport's missile defence systems.
Even as the US troop presence in Afghanistan drew to an end, Pentagon spokesman John Kirby told reporters that it was "a particularly dangerous time right now".
"The threat stream is still real, it's still active, and in many cases it's still specific," he said Monday.
- 'We can't sleep' -
The White House confirmed there had been a rocket attack directed at the airport on Monday, but said airlift operations there were "uninterrupted".
An AFP photographer saw a destroyed car with a launcher system still visible in the back seat.
"The president... has reconfirmed his order that commanders redouble their efforts to prioritise doing whatever is necessary to protect our forces on the ground," a White House statement said.
While there were no reports of fatalities or airport damage from the apparent IS-K rocket salvo, they caused greater anxiety for locals already traumatised by years of war.
"Since the Americans have taken control of the airport, we can't sleep properly," Abdullah, who lives near the airport and gave only one name, told AFP.
"It is either gunfire, rockets, sirens or sounds of huge planes that disturb us. And now that they are being directly targeted, it can put our lives in danger."
An AFP journalist in Kabul said there was a constant sound of planes overhead, with aircraft taking off and landing, as well as jets offering surveillance and protection.
- 'Potential loss of innocent life' -
The United States said Sunday it had carried out a drone strike against a vehicle threatening the Kabul airport that had been linked to the regional Islamic State chapter -- its second targeting IS-K in recent days.
But on Monday, it looked like they had possibly made a terrible mistake.
Members of one family told AFP they believed a fatal error had been made, and that 10 civilians were killed.
"My brother and his four children were killed. I lost my small daughter.. nephews and nieces," Aimal Ahmadi told AFP.
"We are aware of reports of civilian casualties following our strike on a vehicle in Kabul today," Captain Bill Urban, a US Central Command spokesman, said in a statement.
"We would be deeply saddened by any potential loss of innocent life."
In recent years, the Islamic State's Afghanistan-Pakistan chapter has been responsible for some of the deadliest attacks in those countries.
They have massacred civilians at mosques, public squares, schools, and even hospitals.
While both the Islamic State and the Taliban are hardline Sunni Islamists, they are at times also bitter foes -- with each claiming to be the true flag-bearers of jihad.
Last week's suicide bombing at the airport was one of the deadliest bombings for civilians in Kabul in recent years, and led to the worst single-day death toll for the US military in Afghanistan since 2011.
The IS threat has forced the US military and the Taliban to cooperate in ensuring security at the airport in a way unthinkable just weeks ago.
The Taliban have already started taking over areas vacated by US forces.
- Taliban leader -
The Taliban have promised a softer brand of rule compared with their first stint in power, which the US military ended because the group gave sanctuary to Al-Qaeda.
But many Afghans fear a repeat of the Taliban's brutal interpretation of Islamic law, as well as violent retribution for working with foreign militaries, Western missions or the previous US-backed government.
On Sunday, the Taliban revealed their supreme leader Hibatullah Akhundzada was in southern Afghanistan and planning to make a public appearance.
"He is present in Kandahar," said Taliban spokesman Zabihullah Mujahid, referring to the movement's spiritual birthplace.