Although there was no immediate claim for responsibility, the blast occurred in Kunduz, capital of Kunduz Province. However, militants of the Islamic State group have a long history attacking Afghanistan's Shiite minorities.
Dost Mohammad Obeida, deputy chief of police for Kunduz, stated that "majority" of the victims had been killed. According to him, the suicide bomber may have attacked the mosque after mingling with the worshippers.
Obaida stated, "I assure my Shiite brothers the Taliban are ready to ensure their safety," and that an investigation was ongoing.
A confirmed death toll of many would mark the highest number of deaths since the U.S. and NATO forces departed Afghanistan at the end August when the Taliban took over control of the country. The Taliban were the targets of a string of deadly attacks by IS rival militants. These included ambushes and an explosion at Kabul's mosque.
The Kunduz explosion occurred during Friday's prayer service at Gozar-e-Sayed Abad Mosque. The Friday noon prayer at the Gozar-e-Sayed Abad Mosque is the main event of the Muslim religious week. Moscheles are often crowded. Witness Ali Reza claimed that he was praying at time of explosion and saw many casualties.
Photographs and video of the scene show rescuers transporting a body wrapped up in blankets from the mosque to an ambulance. The blood covered the steps leading to the mosque's entrance. The floor was covered in debris from the blast, and the ceiling of the mosque was charred black.
Hussaindad Rezayee a local resident said that he ran to the mosque immediately after the blast. He said, "I was at home working on construction, when the explosion occurred." "I went to the mosque to search for my relatives. It was full."
Zabihullah Mujahid, chief Taliban spokesperson, stated that the Shiite mosque had been the target and that many worshippers were injured and killed. According to him, the Taliban special forces arrived on the scene and were conducting an investigation into the incident.
The Taliban leadership is facing a growing threat by the Islamic State affiliate in Khorasan. IS militants have increased their attacks on rivals, including recent bombings in Kabul.
IS also declared war against Afghanistan's Shiites, and has claimed responsibility for many of the most severe attacks on the community, including the attacks on their mosques and in Kabul's western province of Herat.
The United Nations Mission in Afghanistan condemned Friday’s attack and said it was part of "a disturbing pattern of violence" against religious institutions.
IS claimed that a bombing outside Kabul's Eid Gah Mosque on Sunday killed at least five civilians. On Wednesday, another attack on a madrassa (religious school) in Khost was not reported.
Local Islamic State affiliate claimed responsibility for the August 26 bombing, which killed at least 169 Afghans as well as 13 U.S. military personnel near Kabul Airport in the last days of the chaotic American withdrawal from Afghanistan.
Since the U.S. withdrawal, IS attacks have been concentrated in eastern Afghanistan (the regional base of the IS affiliate) and Kabul.
Ethnic Hazaras are a majority Shiite group that make up about 6% in northern Kunduz province. A large proportion of the province's population is ethnic Uzbek, making it a target for the IS. This militant Islamic Movement of Uzkistan is also close to the province.
Friday's attack by IS if it claims responsibility will be troubling for Afghanistan's neighbors in northern Central Asia and Russia. Russia has long courted the Taliban as an ally against the growing IS in the region.