DAMASCUS, Jan. 15 (Xinhua) -- Intense battles raged on Sunday in a water-rich valley northwest of Damascus, a day after a truce was breached by rebels' killing of a government envoy, a military source said on condition of anonymity.
The Syrian army backed by the Lebanese Hezbollah fighters reached the outskirts of Ain Fijeh spring in the Barada Valley near Damascus, as part of a wide-scale offensive to recapture the spring, the main water source feeding Damascus' over five million people, who have been struggling with the scarcity of water since the rebels shut off the spring on Dec. 22.
This comes a day after rebels with the al-Qaida-linked Nusra Front fired sniper shots at maintenance workers, who entered the area to fix the spring to restore the water flow to Damascus.
The rebels also shot dead retired Brig. Ahmad Ghadban, who was tasked by President Bashar al-Assad to supervise the truce and the reconciliation file in Barada.
The truce deal walked on thorny road till it was reached on Wednesday, as the Nusra Front was among the rebels who attempted to repeatedly thwart any understanding with the government.
Part of the deal also included the reconciliation with the rebels who accept the truce with the government, as such rebels will have their records cleared and will be tasked by the government to protect the Barada Valley.
As for those who refuse the truce, the plan was for their departure to the northwestern province of Idlib.
The deal also provides for the entry of government workers to fix Ain Fijeh, which sustained damage during the weeks-long battles.
The rebels accused the government forces' shelling of rendering the spring out of service, while the government said the Nusra militants cut off the water, using it as a weapon against the government.
Maintenance workers withdrew on Saturday after the Nusra militants fired sniper shots at them.
Last week, the UN has warned that the water crisis afflicting the Syrian capital may constitute a war crime, without identifying the party responsible for the water crisis.
"In Damascus itself, 5.5 million people have had their water supplies cut or minimized," the UN's humanitarian adviser to Syria, Jan Egeland, said.
The tension in Barada Valley has also threatened a Russian-Turkish brokered truce in Syria.
The truce, or the cessation of hostility agreement which went into effect in Syria on Dec. 30, was hailed by both the opposition and the government alike, each trusting his regional ally.
But as the truce was observed across the country, save for areas under the control of the Islamic State (IS) and Nusra Front, the Barada Valley couldn't enjoy the same respite as cutting the water from the capital seemed a redline to the government.
The government defended its offensive in that area, saying the Nusra Front is a main rebel power behind the water outage, and is excluded from the Russian-Turkish cease-fire deal.
With the heavy shelling on the area, several rebel groups reflected their frustration with the government offensive by announcing freezing their participation in talks on the upcoming negotiations in Astana, the first negotiations to include rebels and government officials in Syria.
The Astana talks are slated for Jan. 23, with no foreseeable solution to the crisis in Barada.