Scores injured amid fatal clashes at Nigeria's Arbaeen march

At least three people were killed when clashes erupted between supporters of an imprisoned Shia cleric and security forces during protests organised alongside an annual religious procession in Abuja, the Nigerian Army said.

Four soldiers “sustained various degrees of injuries," the army said in a statement on Monday night.

AFP photographs of the aftermath showed several bodies of civilians on the ground near police but it was not clear whether they were dead or injured.

IMN spokesman Ibrahim Musa said they had received four bodies but indicated the death toll could be higher as "scores" of people were injured and troops took away others.

"We're trying to verify the number," he told AFP.

Human rights group Amnesty International said reports that troops fired live bullets at protesters were "very disturbing" and would be unlawful if they were unarmed.

The deaths bring to six the number of Islamic Movement Nigeria [IMN] supporters who have been killed in demonstrations since Saturday and heighten concerns about further crackdowns on the group.

On Saturday, three IMN members were also killed during protests in Abuja. The army claimed the protesters attacked a military convoy and tried to steal weapons and ammunition.

The IMN has staged a series of protests demanding the release of its leader Ibrahim Zakzaky, who has been in custody since December 2015 after clashes in the northern city of Zaria.

Then, the military was accused of killing more than 300 IMN supporters and burying them in mass graves.

Zakzaky has been at loggerheads with Nigeria's secular authorities for years because of his calls for an Iranian-style Islamic revolution. Northern Nigeria is majority Sunni Muslim.

The cleric, who is in his mid-sixties and lost the sight in one eye during the 2015 clashes, has only been seen in public twice since he was detained.

Nigeria's government has previously ignored a court order to release Zakzaky and his wife.

In April, at least 115 IMN supporters were arrested during protests in Abuja during which police used teargas and water cannon.

Monday’s Abuja protests were organised during a peak period for Shia’s around the world marking the annual Arbaeen commemoration.

Millions of Shia Muslims from around the world are making their way this week to holy shrines in the Iraqi city of Karbala, a pilgrimage that is as much about community as it is about religion.

The shrines are of the revered Shia imam, Hussein, the grandson of the Prophet Muhammad, and his half-brother Abbas.

The pilgrimage, known in Arabic as the Ziyara, marks the 40th day of mourning of the anniversary of Hussein's 7th century death at the hands of the Muslim Umayyad forces in the Battle of Karbala, during the tumultuous first century of Islam's history.

Hussein was seen by his followers as the rightful heir of the prophet's legacy. When he refused to pledge allegiance to the Umayyad caliphate, he was killed in the battle, cementing the schism between Sunni and Shia Islam.

Hussein's half-brother Abbas was also killed in the battle.

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