Syrian activists threatened a "volcano of rage" on Friday over the killing of civilians by government forces as a deadline set by rebel fighters passed for Damascus to honor a UN-backed ceasefire.
State media called for nationwide prayers in memory of the more than 100 dead, many of them children, near the central city of Houla last week, after an official inquiry pinned the blame on the rebels.
But with international outrage mounting after UN military observers on the ground held the government responsible, the United States sharply upped up the pressure on longtime Syrian ally Russia to end its support for its President Bashar al-Assad's regime.
On the first Friday since the killings in Houla, opposition activists called on Syrians to rise up across the country in honor of the 49 children who were among the 108 dead counted by the UN mission.
"A new volcano of rage is exploding thanks to them," protest organizers said on their Syrian Revolution 2011 Facebook page, which has been a major engine of the 15-month uprising against Assad's rule.
"For those pure souls who sacrificed themselves at the altar of our freedom and sacrificed their blood... tomorrow Friday, we will rise up in such a resounding way, and we promise them, there will be no second Houla," they said.
The main weekly Muslim prayers at noon were set to coincide with a deadline set by commanders on the ground of the rebel Free Syrian Army for the Assad's government to respect a UN-backed peace blueprint or face a sharp escalation of the 15-month uprising.
Under the plan brokered by UN-Arab League envoy Kofi Annan, all sides were supposed to respect a ceasefire from April 12 but it has been broken daily with 64 people killed on Thursday alone, according to a Britain-based human rights watchdog.
The dead included 18 loyalists troops in an indication of the growing toll being exacted by the rebels in a conflict that UN chief Ban Ki-moon again warned on Thursday risked degeneration into an all-out civil war that Syria would never recover from.
State television called for prayers "in all of Syria's mosques" for the Houla dead and for "all the country's martyrs" as the government's own inquiry absolved it of responsibility for the deaths.
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