A view from the Palmyra hotel overlooks the historical Roman ruins of Baalbek in the Bekaa Valley March 14, 2015.Reuters

The Islamic State militants have taken control of ancient ruins in the historical city of Palmyra in Syria, deemed as a world heritage site by UNESCO. 

The Isis fighters have also taken control of the Syrian military's air base and intelligence quarters, as per reports. 

Isis stormed into the city on Wednesday and wrested control from the Syrian army, as the group continues to advance in the war-torn nation. 

Palmyra houses remnants of a 2000-year-old oasis civilisation, and several structures such as temples and theatres are still standing. 

Called by the locals as the 'Bride of the Desert', the Roman-era relics have been termed a UNESCO World Heritage site. 

The ancient ruins, however, may be destroyed by the Islamic State as they have done in other historical towns they have captured over the last year. 

"The fear is for the museum and the large monuments that cannot be moved. This is the entire world's battle," Maamoun Abdulkarim, Syria's director-general of antiquities and museums told The Independent. 

For the Syrian government, however, a bigger threat from the fall of Palmyra is that it will also bring Isis closer to Damascus and Homs.