BAMAKO, Mali - A violent attack in the West African nation of Mali on Saturday has left at least one UN peacekeeper dead.

The attack, by an armed group against the United Nation's Integrated Stabilization Mission for Mali (MINUSMA) took place in Timbuktu, an ancient city north of the Niger River and the capital of the Timbuktu Region on Saturday.

The peacekeeper killed was from Nigeria. Another Blue Helmet injured in the assault was also from Nigeria.

The attack has drawn strong condemnation from United Nations Secretary-General António Guterres. 

Mr. Guterres is "deeply saddened at the death of a Nigerian peacekeeper who succumbed to his wounds following the armed attack by unidentified assailants in Timbuktu", his spokesperson, Stéphane Dujarric,  in a statement issued Saturday night.

The UN chief expressed his "heartfelt condolences" to the bereaved family and the government of Nigeria and "wished a speedy recovery to another Nigerian peacekeeper who was wounded in the same attack."

He also wished a "swift recovery to three Chadian peacekeepers," who were wounded when their mine-protected vehicle hit an improvised explosive device in Tessalit, Kidal region. 

The Secretary-General said: "attacks targeting United Nations peacekeepers may constitute war crimes under international law" and called on the Malian authorities to "take swift action to identify the perpetrators of these attacks and promptly bring them to justice."

"The Secretary-General reaffirms the solidarity of United Nations with the people and the government of Mali and its support to their quest for peace and stability", Mr. Dujarric said.