BAMAKO, Mali - Ten United Nation peacekeepers have been killed in what the UN has described as a 'terrorist attack,' in northern Mali.

The 'blue helmets' attached to the United Nations Stabilization Mission In Mali, MINUSMA, were killed on Sunday when the mission's camp in Aguelhok, in the Kidal region, northern Mali came under attack. 

The UN Secretary-General, Antonio Guterres, strongly condemned the attack which also injured twenty five other peacekeepers.

The peacekeeping force were from another African country, Chad.

Mali, a landlocked country in West Africa, has been subjected to a heightened level of violence in the centre and northeastern areas of the country for at least the past six years, since a failed coup attempt..

It is understood militants ambushed the MINUSMA camp on Sunday

"MINUSMA forces responded robustly and a number of assailants were killed," a statement by Secretary-General Guterres's spokesperson read. 

The UN chief conveyed his "heartfelt condolences to the government of Chad, and the families and loved ones of the deceased," and wished a swift recovery to the injured, paying tribute to the dedication and courage of the men and women serving in MINUSMA "at great personal risk and sacrifice." 

MINUSMA is considered the most dangerous mission to serve in as a UN 'blue helmet.'

Mr. Guterres called on the Malian authorities, as well as the signatory armed groups to the peace agreement, to "spare no effort" in identifying the perpetrators of this attack so that they can be brought to justice as swiftly as possible. 

Recalling that attacks targeting UN peacekeepers may constitute war crimes under international law, he reaffirmed that "such acts will not diminish the resolve of the United Nations to continue supporting the people and Government of Mali in their efforts to build peace and stability in the country."

The head of the mission, Mahamat Saleh Annadif, strongly condemned the attack as well. "This complex and cowardly attack shows how determined terrorists are to sow chaos," he said. "This requires a robust, immediate and coordinated response from all the forces to destroy the threat of terrorism in the Sahel."

"Working closely with its partners, MINUSMA will remain proactive and will not let this barbaric act go unpunished," he stated.