Syria’s army dispatched reinforcements to Palmyra in a bid to push back jihadis who advanced Friday to within touching distance of the ancient city, officials and a monitor said, AFP reports.

“Islamic State group jihadis are now one kilometer from the archeological site of Palmyra,” Rami Abdel Rahman, director of activist group the Syrian Observatory for Human Rights, told AFP.

UNESCO describes Palmyra as a heritage site of “outstanding universal value.”

The ancient metropolis stood on a caravan route at the crossroads of several civilisations and its 1st and 2nd century temples and colonnaded streets mark a unique blend of Graeco-Roman and Persian influences.

Since ISIS’s offensive began Tuesday night, more than 138 combatants – including 73 soldiers and 65 jihadis – have been killed.

But the governor of central Homs province, where Palmyra is located, said the situation was “under control.”

“The army has sent reinforcements and it is bombing the (IS) positions from the air,” said Talal Barazi.

According to Barazi, the inner city houses about 35,000 people, including displaced Syrians who fled there after their hometowns were engulfed in violence, and the suburbs host roughly another 35,000.