The Syrian Democratic Forces (SDF) on Friday (July 14th) captured a new district from the "Islamic State of Iraq and Syria" (ISIS) in Syria's al-Raqa, but struggled to hold their positions against suicide car bombers, AFP reported.

The Arab-Kurd alliance seized the eastern Batani district from ISIS on Thursday.

"Late Thursday, they began an offensive on neighbouring al-Rumeilah," said Syrian Observatory for Human Rights head Rami Abdel Rahman.

Clashes were raging on Friday as ISIS deployed defensive tactics: weaponised drones, snipers and improvised explosive devices (IEDs), Abdel Rahman said.

A 30-year-old SDF fighter near al-Rumeilah, who identified himself as Abu, said suicide attackers were on Thursday using explosives-laden vehicles to hold back the SDF.

"They are sending booby-trapped cars towards our positions, and as they fall back, they are laying mines," he said, adding that civilians "cannot move. They cannot leave during the day because of snipers".

Abu said his unit had managed to open up an escape route for al-Rumeilah residents.

According to Abdel Rahman, ISIS has slowed down the SDF's push in other parts of al-Raqa, including the Old City.

"The SDF is struggling to hold newly seized positions in the Old City because of intense sniping and escalating attacks by drones carrying bombs," he said.