At least 10 peacekeepers from Chad have been killed and 25 others wounded in an attack on a United Nations camp in northern Mali, according to the world body.
Al-Qaeda in the Islamic Maghreb (AQIM) claimed responsibility for Sunday's attack, saying it was "in reaction" to the visit to Chad by Israeli Prime Minister Benjamin Netanyahu, according to the Mauritanian Al-Akhbar news agency, which regularly receives statements from this armed group.
UN Secretary General Antonio Guterres condemned what he described as a "complex attack" on the UN camp in Aguelhoc, some 200km north of Mali's Kidal region towards the border with Algeria, and called for the perpetrators to be brought to justice.
According to residents, the attackers came on motorcycles and cars.
"MINUSMA forces responded robustly and a number of assailants were killed," UN spokesperson Ivan Dujarric said, referring to the UN peacekeeping mission in Mali.
Mahamat Saleh Annadif, the UN envoy for Mali, condemned what he called a "vile and criminal" attack.
"Peacekeepers of the MINUSMA force at Aguelhok fought off a sophisticated attack by assailants who arrived on several armed vehicles," he said in a statement.
The attack "illustrates the determination of the terrorists to sow chaos".
He added the attack demanded "a robust, swift and concerted response".
Worsening violence
Mali is under threat from a number of armed groups affiliated with and the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) groups.
The UN has deployed about 12,000 troops and police in its MINUSMA peacekeeping mission in Mali, which ranks as the most dangerous country for the peacekeepers.
Mali, the eighth largest country in Africa and one of the poorest in the world, has been struggling to return to stability after al-Qaeda-linked fighters took control of the northern areas of the country in early 2012, prompting France to intervene militarily.
The fighters were routed in a French-led military operation in 2013, but large stretches of the landlocked Sahel state remain out of government control.
A peace deal between the government and armed groups was signed in 2015, but its implementation has been slow, while attacks continue in central and northern parts of the country.
Earlier this month, both France and the United States criticised the authorities in Mali for their failure to stem the worsening violence.