“Those responsible” must be “swiftly brought to justice,” said the Secretary-General in a statement released by his Spokesperson’s office.

Guterres also expressed his continued concern over the persisting violence in the region and urged all actors to “work together to bring peace and stability to the country.”

The UN chief extended his condolences to the families of the victims as well as to the Government and people of Nigeria, and wished a speedy recovery to those injured.

According to media reports, at least 51 people – including children – were killed in Saturday's attack on Gwaska village, located about 230 kilometres (140 miles) north-west of the capital, Abuja.

Last month, 14 miners were reportedly killed in an attack by gunmen in the same area.

The country’s north-east, meanwhile, has been facing a long-running Boko Haram insurgency that has claimed tens of thousands of lives and driven over two million people from their homes