Five Togolese UN peacekeepers were killed and another was seriously injured when unidentified gunmen ambushed them in central Mali on Sunday, according to the UN mission in the country.
The UN Multidimensional Integrated Stabilization Mission in Mali, MINUSMA, said the attack took place near Sevare town.
"[Mr. Ban] observes with sadness that this latest attack on MINUSMA has taken place on the International Day of UN Peacekeepers [May 29], when the men and women serving under the United Nations flag with honor, courage and dedication are to be honored," a UN statement said.
The attacks against Malian and international peacekeepers have intensified this month, especially in the northern region where terrorist groups are said to be active.
Since the beginning of the year, gunmen have attacked MINUSMA over a dozen times, killing at least 23 staff members.
On Friday, five Malian soldiers were killed and four others injured in a mine explosion in Mali's northern Gao region.
On May 18, five Chadian peacekeepers were killed and three others seriously injured in an ambush claimed by Ansar Dine, a group said to be closely affiliated with Al Qaeda in the Islamic Maghreb.
Violence in Mali began in 2012 when armed groups launched attacks against government forces with the intention of bringing about independence of the Azawad region in the northern part of the country.
Insurgents are still very active in the country despite the presence of UN and French forces.
MINUSMA was deployed in Mali on July 20