Jake Sullivan, National Security Advisor to US President Joe Biden, had said on Sunday that there is an acute and "persistent" threat to the continuing evacuations from the Afghan capital from Isis-K, which takes its name Khorasan from that used by a series of Muslim imperial rulers for a swath of land stretching from Iran to the western Himalayas.

 

The warning, which focused attention on a group that has hitherto had a very low international profile, was echoed this week by British and Western European officials.

 

Many have been worried by an intensification of attacks linked to Isis-K in recent months.

 

Isis-K was founded just under six years ago after two representatives of Isis made their way to Balochistan, the south-western province of Pakistan, for a meeting with a small group of disaffected Taliban commanders and other extremists who had been fighting in the region but felt marginalised within the jihadist movement there, The Guardian reported.

 

The main Isis parent organisation was then approaching its zenith - seizing swaths of Syria and Iraq after a lightning campaign. The group had begun plotting its global expansion even before the victories that brought it to international attention and set about establishing affiliates all over the Islamic world.

 

Isis and Isis-K believe the Taliban have abandoned the Islamic faith because of their willingness to negotiate with the US, their apparent pragmatism and their failure to apply Islamic law with sufficient rigour, The Guardian report said.

 

A blast rocked the Kabul airport, which is thronged by crowds of desperate Afghans seeking to flee the country after the Taliban takeover, on Thursday, causing numerous casualties, including US personnel. There was also a blast at a nearby hotel, causing more casualties.

 

As per sources, bodies were scattered on the roads after the explosions. Sporadic gunshots were also heard for a while, Khaama News reported.

 

Pentagon spokesperson John Kirby has confirmed the incident.

 

Images said to be from the aftermath of the attack outside Kabul airport appear to show injured people with bloodied clothes being moved in wheelbarrows.

 

Some of the pictures, posted to Twitter by Afghanistan's Tolo news agency, show men, women and children - some with makeshift bandages around their heads - fleeing the scene.

 

The BBC reported that a Taliban official has said that at least 11 people have been killed in the attack at Kabul airport.

 

The official said the numbers included women and children, while many Taliban guards have also been wounded.

 

Both explosions took place near the Abbey gate entrance to the airport where large numbers of Afghan refugees had gathered over the past several days.

 

The US Embassy in Kabul had sent out an alert early on Thursday, telling US citizens not to travel to the airport "because of security threats outside the gates", the New York Post reported.

 

Senior US officials told a news wire that the warning was related to specific threats involving ISIS and potential vehicle bombs.

 

The US State Department security alert also told Americans who where at three specific airport gates to "leave immediately", without further explanation.

 

"Because of security threats outside the gates of Kabul airport, we are advising US citizens to avoid traveling to the airport and to avoid airport gates at this time unless you receive individual instructions from a US government representative to do so," the statement read.

 

"US citizens who are at the Abbey Gate, East Gate or North Gate now should leave immediately," it added.