DAKAR  - The International Criminal Court's prosecutor on Sunday warned the rebels to stop destroying ancient Islamic shrines in northern Mali's Timbuktu, saying it amounted to a war crime.

"My message to those involved in these criminal acts is clear: stop the destruction of the religious buildings now. This is a war crime which my office has authority to fully investigate," Fatou Bensouda told AFP in an interview. She said that Mali was signatory to the Rome Statute which established the ICC, which states in Article 8 that deliberate attacks against undefended civilian buildings which are not military objectives are a war crime. "This includes attacks against historical monuments as well as destruction of buildings dedicated to religion," said Bensouda. The hardliners who have occupied the whole of northern Mali, have in two days smashed seven ancient tombs in Timbuktu, a fabled city which dates as far back as the fifth century as a trading center and intellectual capital.

They have also threatened to destroy the city's three ancient mosques, one of which dates back to 1327.

The rampage came after UNESCO listed the city as an endangered site because of the continuing violence in northern Mali and in the wake of an attack on a 15th century tomb in May. The extremists consider shrines idolatrous.

A spokesman for Ansar Dine, Sanda Ould Boumama, said on Saturday that the group was acting in the name of God and would "destroy every mausoleum in the city. All of them, without exception".

Bensouda said her office was still in the process of collecting information, and the next step would be to open a preliminary investigation to determine whether criminal investigations would be launched against those responsible.

"Those who are destroying religious buildings in Timbuktu should do so in full knowledge that they will be held accountable and justice will prevail," she said.