A powerful bomb exploded Friday near a Shiite Muslim religious gathering in Kabul, Afghanistan, killing at least eight civilians and wounding 18 others.

The regional branch of the self-proclaimed Islamic State terrorist group took responsibility for the attack.

Eyewitnesses said members of the minority group, including women and children, were busy with annual mourning rituals in a Shiite-dominated western neighborhood of the Afghan capital when the blast struck.

Taliban spokesman Zabihullah Mujahid on Twitter confirmed the casualty toll, saying the bomb was planted in a pushcart and all of the victims were "innocent civilians."

The government "strongly condemns this cowardly act," Mujahid said, adding that the attack was the work of "the enemies of Islam" and Afghanistan. He did not elaborate.

The Afghan branch of Islamic State, known as Islamic State Khorasan Province or ISIS-K, claimed credit for plotting the deadly bombing and said it had killed and wounded 20 people.

Taliban raid

On Wednesday, Taliban security forces raided an "important" ISIS-K cell in the Afghan capital, killing four militants and capturing another alive in the ensuing gunfight. Mujahid said in a post-raid statement that the militants were "planning to attack our Shiite compatriots during ongoing Muharram rituals."

The Sunni-based ISIS-K has claimed almost all the attacks on Shiite gatherings and worship places in Afghanistan in recent years.

The Taliban have conducted regular operations against ISIS-K hideouts in Kabul and elsewhere in the country, claiming they have significantly degraded the terrorist group.

Anti-US protests

The bombing came on a day when Afghans took to the streets across major cities, including Kabul, to protest against an American drone strike that killed fugitive al-Qaida leader Ayman al-Zawahiri early Sunday.

Footage on state-run Afghan TV showed protesters carrying banners reading "America is a liar," "Down with America" and 'Joe Biden, stop lying.' Rally leaders condemned the airstrike as a violation of Afghan sovereignty and international law.

U.S. President Joe Biden confirmed late Monday the killing of the 71-year-old Egyptian terror mastermind in the aerial missile raid against his safe house in a posh neighborhood in the heart of the Afghan capital.

Afghans in Badghis province shout anti-U.S. slogans Aug. 5, 2022, during a demonstration against the recent U.S. drone strike in Kabul that killed al-Qaida chief Ayman al-Zawahiri.

Friday's rallies, apparently organized by the Taliban, came a day after the ruling Islamist group claimed it had 'no knowledge' al-Zawahiri was residing in Kabul and warned of unspecified "consequences" if Washington breached Afghan territorial sovereignty in the future.

The Taliban said the drone attack was a violation of international law and the agreement they signed with the U.S. in February 2020 in Qatar, which called for the U.S. troop withdrawal in exchange for the then-insurgent group's counterterrorism assurances.

The Biden administration described the assassination of al-Zawahiri, who carried a $25 million U.S. bounty on his head, as the biggest blow to the al-Qaida network since 2011, when American special forces chased and killed its fugitive founder, Osama bin Laden, deep inside neighboring Pakistan.

9/11 planners

Washington said bin Laden and al-Zawahiri orchestrated the September 2001 attacks on the U.S.

The Taliban seized control of Afghanistan last August when the Western-backed government and its security forces collapsed in the face of the insurgent assaults and all U.S.-led international forces withdrew from the country after 20 years of military intervention.

Taliban leaders have repeatedly assured the global community, in line with the February 2020 pact, that they would not allow any group, including al-Qaida, to use Afghan territory for terrorist attacks against other countries.

Washington said the presence of al-Zawahiri in Kabul was a violation of the pact by the Taliban.

The drone attack came as the Taliban were preparing to mark their first year in power August 15. It has dealt a serious blow to the hardline group's efforts to seek international legitimacy to its rule in Kabul and removal of economic sanctions.

No country has yet recognized the Taliban government, citing restrictions the Islamist group has placed on women's access to work and education as well as other violations of human rights of Afghans.