BAMAKO (Reuters) - An al Qaeda-linked militant group has said it is still waging war in Mali, dismissing a report that it had agreed a ceasefire as “completely baseless”.

Ansar Dine released a statement expressing its “utmost surprise” at the announcement by the head of the West African nation’s top Islamic authority, according to a report by the SITE monitoring group late on Tuesday.

Mahmoud Dicko, president of Mali’s High Islamic Council, had said on Monday that he had received news from Ansar Dine’s Tuareg commander Iyad Ag Ghali that it would halt attacks that have killed dozens of civilians, soldiers and U.N. peacekeepers.

Dicko did not give details of the agreement at the time and has not been available for comment since.

Ansar Dine and other Islamist groups have recently intensified their insurgency in Mali, carrying out more than 60 attacks on U.N. and other targets since May and spreading south into areas previously deemed safe.

The groups hijacked a separatist Tuareg rebellion in 2012 to seize major towns in Mali’s vast desert north and declare sharia, or Islamic law. Forces from former colonial power France drove them back a year later, but they have kept bases in remote desert locations.

Earlier this week, Ansar Dine said it had attacked a French military barracks inside a U.N. camp in the northern city of Kidal.

A spokesman for the U.N. mission known as MINUSMA said several shells hit the base on Sunday, damaging three helicopters.