Nearly 300 cultural heritage sites in Syria have been damaged, many severely, by the country's civil war, a UN agency said in a report released on Tuesday.

The United Nations Institute for Training and Research (UNITAR) said that detailed analysis of satellite imagery from 18 sensitive areas had shown that 24 sites had been destroyed, and 104 severely damaged. A further 85 had suffered moderate damage, while 77 were possibly damaged, it said.

The report said that UNESCO World Heritage sites in Aleppo, Damascus, the ancient city of Palmyra and the Crusader castle known as Crac des Chevaliers (shown above) had sustained major damage.

The commercially available satellite imagery used for the report - collected by UNOSAT, a UN instituted based in Geneva - also covered other World Heritage sites in the capital, Damascus, the historical northern city of Aleppo, Bosra and the Dead Cities of northern Syria.

'Alarming testimony'

"Looting, destruction from aerial bombardment and other explosions, as well as infrastructure construction at cultural sites significantly threatens the heritage to future generations of these historic structures and objects," the UN said in a statement.

The Temple of Baal in Palmyra is internationally famous

The UN said the report was "alarming testimony of the ongoing damage that is happening to Syria's vast cultural heritage" and called on both Syria and the international community to do more to protect them.

Syria's civil conflict broke out 2011, pitting rebels from several different groups against the government of President Bashar al-Assad. The Britain-based opposition monitoring group Syrian Observatory for Human Rights estimates that at least 200,000 people - some 63,000 of them civilians - have been killed in less than four years of fighting.

tj/es (AP, AFP)