“Very sadly informed that respected cleric [Haqqani] was martyred in a cowardly attack by enemies,” Bilal Karimi, a spokesperson for the Taliban administration, said in a statement.

Soon afterwards, Isis claimed responsibility for the attack.

Four Taliban sources told Reuters that the attacker was someone who had previously lost his leg and had hidden the explosives in a plastic artificial leg.

“We are investigating who this person was, and who had brought him to this important place to enter the personal office of Sheikh Rahimullah Haqqani. It’s a very huge loss for the Islamic Emirate of Afghanistan,” said a senior Taliban official at the interior ministry, referring to the group’s name for its administration.

Haqqani was one of the most “prominent advocates for the Taliban, and one of the biggest of them who incited to fight” Isis, the monitoring group SITE said, translating a statement from Isis.

Haqqani had survived previous attacks, including a blast in the northern Pakistani city of Peshawar in 2020, which was claimed by Isis and killed at least seven people.

After Haqqani’s death, many Taliban officials paid tribute to him on social media. “You have fulfilled your responsibility. Destiny cannot be prevented, but the Muslim community has been orphaned,” wrote Mobin Khan, a former spokesperson for the Kabul police.

Islamic organisation Tanzeem-e-Islami added: “We vehemently condemn the suicide blast in #Kabul in which the Islamic scholar, Sheikh Rahimullah Haqqani was martyred.

“The malevolent forces have resorted to perpetrating the worst kind of terrorism in Afghanistan.”

Journalist Muhammad Haris wrote: “Right after the return of the Islamic Emirate, Sheikh Rahimullah Haqqani started teaching public classes in Kabul. I have watched many of his lectures. He had a broad understanding of the Muslim and global affairs, and an influence. May Allah forgive him and grant him high Jannah.”