Iraq has sent an entire army division to the Syrian border a day after Syrian rebels took control of a number of border crossings.
The Abu Kamal crossing was captured after a battle with Syrian government forces.
Rebels have also taken control of two posts at Bab al-Hawa and Jarablus along the border with Turkey.
Meanwhile there are gun battles in the capital Damascus for a sixth day in a row.
Al Jazeera's Khadija Magardie reports.