The killings of more than 100 Syrian civilians, including nearly 50 children, provoked outrage around Syria and worldwide Sunday as horrific images of the bodies in Houla spread across the internet.
Videos posted Sunday on YouTube show demonstrations in cities around the country, including Damascus, Daraa, Idlib, and the suburbs of Hama.
"Oh Houla, we are with you until death," protesters chanted in Daraa. And a demonstration in Idlib showed a U.N. vehicle among protesters. In the Hama suburbs, demonstrators called for President Bashar al-Assad to step down.
Syria's government denied its troops were behind the bloodbath in Houla, and a Foreign Ministry spokesman denounced what he called a "tsunami of lies" against President Bashar al-Assad's government. But the 14-month-old clampdown continued, with opposition activists reporting another 26 people -- including five children and three women -- killed across the country on Sunday.
At the United Nations, where Security Council members huddled for closed-door talks on the crisis, a senior U.N. official said said the death toll from Friday's killings in Houla had now grown to 108. Herve Ladsous, the undersecretary-general for peacekeeping operations, said that figure came from Maj. Gen. Robert Mood, the head of the U.N. monitoring mission in Syria.
Sausan Ghosheh, the spokeswoman for the U.N. mission, said the dead included 34 women and 49 children under the age of 10.
Britain and the United States condemned the Houla massacre; so did Israel, in a rare public statement on the 14-month-old Syrian conflict.
U.N. monitors visited the town over the weekend, releasing video Sunday that depicts bodies being loaded into a truck and others being prepared for funerals. One man tells the monitors that shelling began after Friday prayers, and the killings didn't stop until 2 a.m. Saturday.
Opposition activists said killings began with a mortar bombardment, followed by a rampage by government-allied militias. Video posted over the weekend showed opposition activists displaying the bloodied remains of more than 10 children, including some with limbs blown off or skulls torn open. In another, medics treated a crying infant whose chest was covered in bandages.
Syrian officials say government troops are fighting to protect their people from "terrorist gangs." But Alex Thompson, a reporter for Britain's ITV television network who was in Houla, said its residents appeared to be voting with their feet.
"There are lots of civilians in the rebel-held areas. They are not apparently frightened of the fighters. They are speaking openly to the United Nations," Thomson told CNN. "In the areas of the town held by the army, there is nobody -- it's a ghost town."
But Foreign Ministry spokesman Jihad Makdissi told reporters Sunday in Damascus, "We deny that the Syrian armed forces were responsible of what took place in Houla." And on state-run media, the Syrian regime said "al Qaeda-linked terrorist groups committed two horrible massacres against a number of families in the towns of al-Shumariyeh and Taldo in the countryside of Homs province."
The state report also showed gruesome images of children spattered with blood.
CNN can not independently confirm details from Syria nor the authenticity of videos, however, as the Syrian government strictly limits access by foreign journalists.
The White House joined the condemnation Sunday afternoon, with National Security Council spokesman Tommy Vietor saying the United States was horrifed by "credible reports" of the massacre, "including stabbing and ax attacks on women and children."
"These acts serve as a vile testament to an illegitimate regime that responds to peaceful political protest with unspeakable and inhuman brutality," Vietor said in a written statement.
And British Foreign Secretary William Hague said he had summoned the Syrian charge d'affaires in London to his office "so that we can underline our absolute horror at what has happened."
"It is a familiar tactic of the Assad regime to blame others for what is happening in their country, to try to get out of responsibility for the scale of death and destruction," he said.
The crisis began in March 2011, when peaceful demonstrations modeled on the "Arab Spring" uprisings in Tunisia and Egypt sprang up across Syria. Al-Assad's government responded by turning police and troops on demonstrators -- but the protests spread across the country, with defecting soldiers taking up up arms on behalf of the opposition.
Opposition: 88 killed in 'barbaric act' in central Syria
A cease-fire agreement, brokered by former U.N. Secretary-General Kofi Annan's office, has been in place since April 12 as part of a six-point peace plan. But Col. Qasim Saad Eddine, a spokesman for the rebel Free Syrian Army, said Saturday that it was "no longer possible to abide by the peace plan" after the Houla killings.
"This is a clear evidence that Kofi Annan's plan is dead and a clear indication that Bashar Assad and his criminal gang do not understand anything but the language of force and violence," Eddine said. He urged the U.N. Security Council to authorize airstrikes by member nations against government forces and strategic points.
A U.N. report issued Friday said Syrian forces are still using heavy weapons in many areas despite the April cease-fire, and "The overall level of violence in the country remains quite high" despite the presence of U.N. monitors. Monitors have heard the sound of shelling in cities and towns and seen the aftereffects, their report states, while Syrian authorities say they were coming under fire from rebel troops.
Meanwhile, opposition groups effectively control "significant parts of some cities" the monitors state. But the government's stepped-up security crackdown "has led to massive violations of human rights" by Syrian troops and pro-government militias, the report states.
Makdissi, in his remarks Sunday, accused some U.N. countries of "openly working against Syria" and rejected the notion of an armed opposition in the country.