ISIS have carried out threats to destroy structures in the Unesco-protected historical site within the Syrian city of Palmyra.
Photos taken by the group have shown a tomb being blown up and a shrine which lies just outside the main Unesco site.
It is suspected that ISIS are already prepared to destroy the most famous monuments including the distinctive Roman amphitheatre. As fears were raised last month.
ISIS believe that nothing should predate the birth of Mohammed (570 AD).
The destruction was likely a warning to President Bashar al-Assad’s forces if they do not stop advancing on ISIS.