Five suspects detained in connection with the murder of a Nigerian Christian market trader have been released without trial.
Bridget Agbahime, 74, was murdered in Kofar Wambai market in the Nigerian state of Kano on 2 June following a false accusation of blasphemy.
Dauda Ahmed, Zubairu Abdullahi, Abdulmumeen Mustafa, Abdullahi Abubakar and Musa Abdullahi were arrested for charged with "inciting disturbance, joint act, mischief and culpable homicide".
According to Christian Solidarity Worldwide, Mr Ahmed had been harassing Mrs Agbahime, the wife of a pastor, for a long time.
On the day of her murder, Mrs Agbahime asked Mr Ahmed to move away from her shop and he began shouting that she had committed blasphemy.
A mob of 500 people battered the shop keeper to death after dragging her outside.
On 6 November, Chief magistrate Muhammad Jibril discharged the five suspects who were arrested and terminated the case against them.
In a statement issued on 6 November, the Enugu State Chapter of the Christian Association of Nigeria urged Nigeria's Federal Government to revisit the case.
Christian Solidarity Worldwide's Chief Executive Mervyn Thomas said, "The unconditional release of these suspects, one of whom we believe to be directly implicated in, if not responsible for this brutal murder, is both inexplicable and unacceptable.
"The continuing lack of consequences will increase the impunity surrounding blasphemy accusations, which are used to justify the most extreme acts of lawlessness, regardless of the character and integrity of the person making the accusation. In order to combat impunity and strengthen the rule of law, it is essential that no person or social grouping is seen as being above the law. CSW therefore urges the Federal authorities to ensure this decision is reviewed and that the perpetrators of this appalling murder face justice," Mr Thomas concluded.
Mrs Agbahime was the second person in northern Nigeria to be killed by a mob during 2016 following allegations of blasphemy.
Nigeria is home to the biggest population of Christians in Africa but they only make up a small percentage of the population in the north of the country.
Tensions between Muslims and Christians mean that Nigeria is regularly plagued by religious conflict.