TIMBUKTU, Mali - A resident of the northern Mali city of Timbuktu says Islamists who control the town are trying to destroy tombs classified as UNESCO World Heritage sites.

Ali Yattara said Saturday that the Islamists began attacking the saints' tombs with shovels. He says they said they were responding to UNESCO's request last week that the sites be put on the organization's "in danger" list.

UNESCO has said that two World Heritage sites in Mali — Timbuktu and the tomb of Askia — are threatened by conflict between competing rebel groups who have taken over the north.

Islamist fighters with ties to al-Qaida have declared that they control the northern half of Mali after driving out an ethnic Tuareg separatist group.

Timbuktu was a centre of Islamic learning as far back as the 12th century.