Rebels in Syria say Assad's forces had slaughtered at least 78 people, including women and children, but Assad's people say it was the rebels and the numbers were far fewer. ITN's Paul Davies reports. Warning: Some pictures in this report are disturbing.
Updated at 11:20 a.m. ET: BEIRUT -- United Nations Secretary-General Ban Ki-moon said on Thursday that U.N. monitors were shot at trying to get to the scene of the latest Syrian massacre in which at least 78 villagers were allegedly slaughtered by forces loyal to President Bashar al-Assad.
Opposition activists said up to 40 women and children were among the dead in Mazraat al-Qubeir, near Hama, on Wednesday, posting film on the Internet of bloodied or charred bodies.
Syrian activists say 100 people were killed by government supporters Wednesday in the province of Hama, including many women and children. Meanwhile, diplomatic efforts to quell the crisis continue to stall. NBC's Ayman Mohyeldin reports.
Confirmation of Wednesday's massacre will pile pressure on world powers to act, but they have been paralyzed by rifts pitting Western and most Arab states against Assad's defenders in Russia, China and Iran.
The U.N. chief told the General Assembly that the unarmed observers were initially denied access to the scene in central Hama and "were shot at with small arms" while trying to get there. He did not mention any casualties.
Ban said each day in Syria was seeing more "grim atrocities" and that for many months it had been evident that Assad and his government "have lost all legitimacy."
Any regime that tolerates killings such as one in which 108 people were slain in the town of Houla on May 25 and Wednesday's attack near Hama "has lost its fundamental humanity," he said, condemning "this unspeakable barbarity."
Earlier, Syria's pro-government Addounia TV said U.N. observers had arrived in Mazraat al-Qubeir, but the chief of the U.N. mission said that Syrian troops and civilians had barred them.
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"They are being stopped at Syrian army checkpoints and in some cases turned back," General Robert Mood, the head of the U.N. observer mission, said in a statement earlier on Thursday. "Some of our patrols are being stopped by civilians in the area."
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U.S. Secretary of State Hillary Clinton described the latest reported massacre as unconscionable.
"We are disgusted by what we are seeing (in Syria)," she told a news conference during a visit to Istanbul.
The Syrian state news agency quoted an official source in Hama describing reports from Mazraat al-Qabeer as "completely false," saying security forces had intervened at the request of residents after a "terrorist group committed ... a monstrous crime", killing nine women and children.
Syrian authorities have also denied responsibility for the Houla killings, blaming foreign-backed Islamist militants.
As with the May 25 killings -- which Western powers blame on Assad's troops and loyalist "shabbiha" militia -- the Syrian Observatory for Human Rights said "shabbiha headed into the area after the shelling and killed dozens of citizens, among them women and children."
Shabbiha, drawn mostly from Assad's minority Alawite sect that is an offshoot of Shiite Islam, have been blamed for the killings of civilians from the Sunni Muslim majority. That has raised fears of an Iraq-style sectarian bloodbath and the prospect of a wider regional confrontation between Shiite Iran and the mainly Sunni-led Arab states of the Middle East.
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Reports of mass killings have emerged not even two weeks after a recent massacre that killed about 100 people. NBC's Ayman Mohyeldin reports.
Some 13,000 people have been killed in Syria over 15 months of repression and later armed rebellion.
The main Syrian National Council opposition group responded to reports of the new massacre by calling for stepped-up military assaults on Assad's forces.
The failure of a cease-fire brokered by U.N. envoy Kofi Annan in March to halt the bloodshed has raised questions about its continued worth.
The 300-member group of U.N. truce observers has been in Syria for weeks.
Events in Syria are difficult to verify as state authorities tightly restrict access for international media.
Up with Chris Hayes panelists Colonel Jack Jacobs, MSNBC military analyst; Karam Nachar, an activist who has been working with opposition leaders in Syria; Jeremy Scahill of The Nation magazine; and Josh Trevino of the Texas Public Policy Foundation, discuss whether civil war is inevitable in Syria, and whether there's anything the United States and the world can do to stop it.
Rebel groups inside Syria, which helped escalate what began as popular demonstrations for democracy into what is approaching a civil war, say they are no longer bound by Annan's cease-fire and are calling for more foreign arms and other support.
Western leaders, wary of new military engagements in the Muslim world and especially of the explosively complex ethnic and religious mix that Syria represents, have offered sympathy but shown no appetite for taking on Assad's redoubtable armed forces, which can call on Iran and Russia for supplies.
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In Washington on Wednesday, the United States and Saudi Arabia, among dozens of mostly Western and Arab countries in the Friends of Syria working group, called for further economic sanctions against Syria including an arms embargo, travel bans and tougher financial penalties.
Thirteen men were shot dead at close range in Syria. Activists claim the killers were government militia. The government blames the rebels. NBC's John Ray reports. Some of the images in this report may be disturbing.
Separately, ministers and envoys from 15 countries and the European Union agreed at a meeting hosted by Turkey in Istanbul on Wednesday to convene a "coordination group" to provide support to the opposition but left unclear what this may entail.
The U.S. and its allies in Europe, Turkey and the Arab world also agreed to work on a political transition plan for Syria, hoping to persuade Russia to join a broadened diplomatic effort to ease Assad out of power, a senior U.S. official said.
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But with neither Russia nor China present, and both remaining hostile to the idea of global sanctions against the Syrian government or any Libya-style military intervention, it was unclear what effect the show of unity might produce.
Brutal shelling and attacks have made life inside of Syria's Homs harrowing and for those who try to flee, perilous. NBC's Ayman Mohyeldin reports.
Speaking in Beijing, Russia's foreign minister presented a counterproposal for international action, proposing a conference on Syria but with an emphasis on pressuring opposition groups to respect Annan's peace plan.
Sergei Lavrov criticized the Friends of Syria meetings that the U.S. and its partners have been having for being "devoted exclusively to the support of the Syrian National Council and its radical demands." He said the Russian gathering would, by contrast, put pressure on the Syrian opposition to "end all violence and sit down for talks."
Reuters and The Associated Press contributed to this report.
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