Infighting between two of the most powerful factions in Syria's opposition-held Idlib province has killed at least 14 people in the past 24 hours, AFP reported Wednesday (July 19th).

The fighting pits Tahrir al-Sham, an extremist alliance dominated by the former al-Nusra Front (ANF), against one-time ally Ahrar al-Sham, a powerful Islamist opposition group.

The Syrian Observatory for Human Rights said fighters from the two sides were engaged in clashes across the north-west province that killed 11 fighters and three civilians in the last 24 hours.

"These are the most violent and widespread clashes that have taken place between Ahrar al-Sham and Tahrir al-Sham," Observatory director Rami Abdel Rahman said.

"The clashes are ongoing across all of the province, with territory changing hands... It is an existential battle," he added.

Fighting was reported in several areas, particularly in the town of Sarmada and around the towns of Saraqeb and al-Dana.

Abdel Rahman said both sides had set up multiple checkpoints inside and around Idlib city.

The two groups have clashed before, despite having previously formed the backbone of the alliance that captured most of Idlib in early 2015.

The latest conflict arises partly out of a dispute over Ahrar al-Sham's desire to fly the flag of the Syrian uprising in Idlib city, the Observatory said.