A newly established militant group in Nigeria has claimed responsibility for an attack at a Chevron-owned oil pipeline in the Niger Delta area. The Niger Delta Avengers (NDA) communicated it carried out the attack through its Twitter account, claiming it had warned Chevron "but they did not listen".

The group warned Chevron on 12 May not to carry out repair works at the Valve platform that was blown by the militants earlier in the month.

The latest attack took place days after the Egbesu Mightier Fraternity (EMF), a faction of NDA, warned the Nigerian government it had two weeks to release pro-Biafran leader Nnamdi Kanu and former security aide Sambo Dasuki or it would shut down oil and gas facilities in the country.

NDA is the latest militant organisation to wage war against the Nigerian government due to perceived marginalisation in the Niger Delta. The organisation describes itself as a group of Niger Deltans on a "revolution to free Nigeria from the wicked administration".

The group has warned that attacks against Shell and Chevron were "just the beginning", unless the government meets NDA's demands.

Read more on the Niger Delta Avengers: Nigeria's oil and gas production threatened by new militants

Attacks on oil facilities blamed on the group have partially halted oil production. Meanwhile, Nigeria removed oil subsidy and increased petroleum prices by two-thirds, in a bid to curb an ongoing fuel crisis.

President Muhammadu Buhari has accused the NDA of vandalism and warned that the Nigerian government would deal with the group in the same way it is tackling Boko Haram terrorists in the country's north-east.

British Foreign Minister Philip Hammond said Buhari needed to address the underlying causes of the conflict, amid fears a military confrontation could end in "disaster".

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