Mali's interim government has condemned what it called the “destructive rage” of armed members of the Islamist Ansar Dine group who destroyed historic shrines in the ancient city of Timbuktu Saturday.

In a statement, the government said the attacks amount to war crimes and vowed to pursue those responsible, even possibly in the International Criminal Court.

Saturday's attacks came two days after the U.N. declared Timbuktu, home to 16 ancient mausoleums, as a World Heritage site in need of protection.

Witnesses told VOA that members of Ansar Dine attacked the historic sites with axes, shovels, and machetes, to the deep dismay of the local people. One man said the militants had threatened the townspeople with violence. Another said they had no weapons with which to fight back.

Among the structures destroyed is the mausoleum of a revered 15th-century Muslim saint, Sidi Mahmoud.

Hardline Islamists like the Ansar Dine regard such shrines as sacrilegious, but the sites are an important part of worship for Muslims around the world.

The head of the U.N. cultural agency, Irina Bokova, called the acts “terrible and irreversible.” France has also spoken out against the destruction.

Timbuktu was once an intellectual and spiritual capital, as well as a center for the propagation of Islam throughout Africa in the 15th and 16th centuries. It is home to thousands of ancient manuscripts, preserved in family homes and private libraries under the care of religious scholars.

UNESCO said it decided to place Timbuktu on its endangered list because its sites were “threatened by the armed conflict in the region.”