Islamic State militants have destroyed Palmyra's ancient temple of Baalshamin, Syrian officials and activists say.
Syria's head of antiquities was quoted as saying the temple was blown up on Sunday. The UK -based Syrian Observatory for Human Rights (SOHR) reported that it happened a month ago.
IS took control of Palmyra in May, sparking fears for the site.
It is considered one of the ancient world's most important cultural centres.
The ancient city, which is a Unesco World Heritage site, is famed for its well-preserved Greco-Roman ruins, and the Baalshamin temple, built nearly 2,000 years ago, is one of the city's best-known buildings.
The Islamic State group has destroyed several ancient sites in Iraq. The militants believe any shrines or statues implying the existence of another deity are sacrilege and idolatry, and should be destroyed.
IS "placed a large quantity of explosives in the temple of Baalshamin today [Sunday] and then blew it up causing much damage to the temple," Syrian antiquities chief Maamoun Abdulkarim told AFP news agency.
"The cella (inner area of the temple) was destroyed and the columns around collapsed," he said.
The Baalshamin temple is dedicated to the Phoenician god of storms and fertilising rains, and was almost completely intact.
The oldest parts of the temple are thought to have dated from the year 17AD.
Residents who had fled from Palmyra also said IS had planted explosives at the temple, although they had done it about one month ago, according to the Syrian Observatory for Human Rights.
Last month, IS published photos of militants destroying what it said were artefacts looted at Palmyra.
A week ago, it emerged that the archaeologist who had looked after Palmyra's ruins for four decades, Khaled al-Asaad, had been beheaded by the militant group.
Mr Abdulkarim said the 81-year-old had refused to tell IS where some treasures had been hidden, in an effort to save them.
The group has also published photos of what they said was the destruction of two Islamic shrines near Palmyra, which they described as "manifestations of polytheism".
The modern city of Palmyra - known locally as Tadmur - is situated in a strategically important area on the road between the Syrian capital, Damascus, and the eastern city of Deir al-Zour.
Credit: The BBC