RNA - During the gathering on Wednesday, Iranian doctors, academics and students called on the UN officials to take actions and confront Nigeria for violating human rights laws.
Nigerian security forces took Zakzaky and his wife into custody in December 2015, after a deadly raid that killed more than 300 of his followers and three of his sons.
"Four years after the brutal and unreasonable massacre of the Nigerian people by the government and the violent arrest and torture of Shia Muslims, unfortunately we still witness the silence of the global institutions in reaction to this stark human rights violation," read a statement by the protesters.
Citing several instances of the human rights violations by Nigerian forces, the protesters warned that if the UN doesn't get involved soon, human rights organizations and Islamic nations "won 't allow" this to continue and will take their "humane" rights back.
Members of Islamic Movement in Nigeria (IMN) announced last month that Sheikh Zakzaky was poisoned, citing results of an investigation by the movement's Academic Forum.
Based on the findings, a high-level of toxicity has been diagnosed in the cleric’s blood, which has worsened his health condition.
According to Press TV, Zakzaky’s legal team has long called for his release, saying he is suffering from health issues that require urgent medical care abroad, but the state high court in Kaduna has denied the request.
A team of medics examining Zakzaky in prison have renewed pleas for him to be released, saying levels of the chemical toxic substance — lead — is so dangerously high in his blood that requires an immediate medical treatment.