The United Nations (UN)’s Secretary-General Ban Ki-moon has condemned a recent triple bombing attack by the Boko Haram terrorist group that killed at least 27 people on an island on the Chadian side of Lake Chad.

“The secretary-general condemns the triple suicide attack on the island of Koulfoua on the Chadian side of Lake Chad on 5 December 2015,” read a statement released by Ban’s office on Sunday. “These despicable acts demonstrate yet again the brutality of Boko Haram.”

Ban also offered “condolences to the families of those killed and injured.” Some 80 people were wounded in the Saturday attack.

In recent months, Boko Haram terrorists, who hail from Nigeria, have stepped up attacks and bombings on Chadian villages in the Lake Chad region as well as in neighboring Niger and Cameroon.

On November 9, Chad declared a state of emergency in the flashpoint Lake region, which straddles Nigeria, Cameroon and Niger.

Regional countries have created a joint military force that plays a key role in helping Nigeria fight the terrorist group. Back in February, the four littoral nations of Lake Chad, i.e., Chad, Cameroon, Niger, and Nigeria, launched a military campaign, together with a contingent from Benin, to confront the threat from Boko Haram militants in the region.

Chad has the highest number of forces in the regional 8,700-strong military task force.

The Boko Haram terrorist group, which has pledged allegiance to the Takfiri Daesh militant group, has killed at least 17,000 people, mostly civilians, since it launched its terrorist activities in Nigeria in 2009.

The Takfiri militant group has intensified its campaign of terror since President Mohammadu Buhari came to power in the African country on May 29. Buhari has pledged to eradicate the group.