A nine-month-old child wears Biafran colours at a rally by the Movement for the Actualisation of Sovereign State of Biafra (Massob) in south-eastern Nigeria AFP/ Getty Images

At least 200 people belonging to the Nigerian Movement for the Actualization of Sovereign State of Biafra (Massob) have been arrested when the police raided the movement's headquarters in Okigwe, Imo State.

The mass arrest came a few hours after the Nigerian Police released a statement urging authorities to clamp down on people involved in the violent struggle. The statement read: "This directive becomes imperative owing to recent activities of members of the Movement for the Actualization of Sovereign States of Biafran (MASSOB) and the Indigenous People of Biafra (IPOB) in some parts of the country."

Three Massob coordinators in Anambra State said that the whereabouts of the movement's leader, Chief Ralph Uwazurike, were unknown following the raid, according to a report by the Daily Independent. IBTimes UK contacted members of Massob and Ipob but has not received a response at the time of publishing.

In a previous interview with IBTimes UK, Ikechukwu Opara, a member of Massob, defined the movement as one of "the most influential umbrella groups for the current Biafran struggle, which can only yield results via Massob's ethos of non-violence."

The Nigerian government has accused Massob of violence and Uwazuruike was arrested in 2005 on treason charges. He was released two years later.

In an interview with IBTimes UK, government spokesperson Mike Omeri said the authority does not consider the separatist movements as a threat to the current leadership and defined pro-Biafrans as an "insignificant number of frustrated people who are not a threat to the existence of Nigeria".

He also slammed allegations of violence against pro-Biafrans as "entirely incorrect, misinformation and calculated to create bad blood and tension".

He added: "They [pro-Biafrans] want to create a picture of Nigeria that is not [true]. The government of Nigeria values human rights and has an obligation [to] protect lives."

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