Militant Islamists have reportedly shot two men in cold blood in front of a mosque in the Syrian city of Idlib, charged with having furnished “relief materials to the towns of Al-Fu’ah and Kafriya,” currently under siege by the Sunni radicals.

The UK-based Syrian Observatory for Human Rights attribute the killings to the Islamic faction Jabhat Al-Nusra (al-Qaeda in Levant), who had issued a statement forbidding any material support to the inhabitants of the Shiite towns of Al-Fu’ah and Kafriya, wherether it be foodstuffs or other materials, under pain of death.

The Islamist radicals said that anyone disobeying this injunction would be “executed in the public square” and stated that the decision was made in order to avoid weakening the effect of the siege on Al-Fu’ah and Kafriya by the “Mujahedeen.”

The al-Nusra Front, a radical Sunni group associated with al-Qaeda, has been operating in Syria since 2012 and was born out of the civil war. It has become a highly effective opposition force to the Assad government, and is classified as a terrorist group by Russia, the US and UN. The goal of al-Nusra is the establishment of a Sunni-Islamic emirate in Syria.

On Monday, the Syrian regime signed a truce with representatives of the rebel forces, while explicitly excluding the jihadist groups of ISIS, Al Qaeda and Jabhat al-Nusra.

“The Syrian Arab Republic accepts the cessation of fighting actions on the basis of continuing the military efforts for combating terrorism against the Islamic State in Iraq and Syria (ISIS), Jabhat al-Nusra and other al-Qaeda-linked terrorist organizations according to the Russian-U.S. agreement,” said an official source at the Syrian Expatriates and Foreign Ministry.

During the course of the Syrian Civil War that arose out of the Arab Spring protests of 2011, more than 370,000 people are thought to have be killed in the beleaguered Middle Eastern country, along with another 20,000 presumed to be detained inside regime prisons and some 5,000 more thought to be held in Islamic State jails.

Follow Thomas D. Williams on Twitter