LAGOS, (AA) – At least 21 people are feared dead and dozens more injured Friday afternoon as a suicide bomber attacked a large procession of Nigeria’s Shia members in the northwestern part of the country, according to an official of the religious movement.

The attack occurred in Chiromawa, a village roughly 50 kilometers from the northwestern city of Kano.

“So far, we have 21 persons confirmed dead while dozens were injured. A suicide bomber infiltrated the large procession at Chiromawa and detonated explosives wired to his body as he was being challenged,” Mustapha Potiskum, a leader of the Islamic Movement of Nigeria, told Anadolu Agency over the phone.

The northwest coordinator of the country’s relief agency NEMA confirmed the attack but could not confirm the death toll.

“We just got information about the attack and we have mobilized at the scene. Our men and security agents are at the scene but it is early to say how many persons have died,” Musa Ilallah, northwest NEMA coordinator, told Anadolu Agency.

Potiskum said the procession — dubbed ‘Arbaeen Symbolic Trek — started at the Faje central mosque in Kano on Thursday and was headed to Zaria in the neighboring Kaduna state, where the head of Sheikh Ibrahim el-Zakzaky was due to address members of the Shiite faith. Similar processions were headed to Zaria from other parts of the northern region.

No group has claimed responsibility for the blast.  The violent extremist group Boko Haram has been known to carry out attacks in the region, although Nigeria’s Shia Muslims have claimed in the past that the army was behind previous suicide attacks against them.

The army has denied these claims. Both the Shia community and the Nigerian army had been at odds since 2014 when shots allegedly fired by soldiers at a Shia procession killed 35 people including three sons of el-Zakzaky.