Suspected members of a Syrian Islamist rebel faction tore up the flag of the revolution on Friday at an anti-regime protest in the city of Saraqeb in Idlib province.
Cries of "Unity, Freedom, an Islamic state!" were met by chants of "Unity, freedom, a civil state!" as a scuffle broke out.
In footage posted on YouTube, a man identified as a member of "the Islamic battalion" taunts another demonstrator holding the three-starred banner aloft.
As the flag-bearer takes a swipe at him, two others rush to grab the pole and push him away. One breaks the pole, and angrily throws the symbol of the revolt on the ground.
Saraqeb is home to the full spectrum of opposition forces and has seen protests against Al-Nusra Front take place in recent weeks, despite the hardline group's heavy presence there.
The United Nations says more than 60,000 people have been killed in Syria since the outbreak of a revolt in March 2011 that morphed into an insurgency after the army launched a brutal crackdown on dissent.