(CNN) -- Businesses in several Syrian cities were shuttered Wednesday amid ongoing violence and bloodshed as pressure mounted for an international response to the government crackdown on protesters.
Thirty-three people were killed Wednesday, among them three women and a child, according to the Local Coordination Committees of Syria, an opposition group that organizes and documents protests. Ten people were killed in the city of Homs; 11 in Hama; three in Idlib province; two in Daraa, Damascus and Deir Ezzor; and one each in Qamishli, Zabadani and Raqqa, the group said.
Earlier, the Syrian Observatory for Human Rights, another activist group, said five civilians died in the Hama suburbs when their vehicle was targeted by military forces. In retaliation, army defectors ambushed four military vehicles, killing eight troops, the organization said.
In the city of Daraa, a civilian was killed and three military defectors were wounded in clashes with security forces in the village of al-Lajat, the observatory said. And it said military and security forces stormed the city of al-Harak with heavy machine gun fire, tanks and an armored personnel carrier.
Wednesday marked the latest in a series of bloody days in Syria. On Tuesday, at least 36 people died, according to the LCC. Army defectors killed seven government security forces in a convoy attack in response to the deaths of 11 civilians in Idlib province, it said.
One result of the Syrian regime's nine-month crackdown has been the emergence of an armed opposition group of defectors -- the Free Syrian Army.
CNN cannot independently confirm reports of violence in Syria because the government restricts access by foreign journalists.
"This cannot go on," U.N. Secretary-General Ban Ki-moon said Wednesday. "In the name of humanity, it is time for the international community to act." He cited reports of more than 5,000 dead.
In Washington, the chairman of the House Subcommittee on the Middle East and South Asia, Rep. Steve Chabot, R-Ohio, said at least 300 children were among the dead. "The situation on the ground continues to intensify and the possibility of a civil war breaking out along sectarian lines looms on the horizon," he said in a statement on the Committee on Foreign Affairs' website.
The special coordinator for regional affairs of the Office of the U.S. Special Envoy for Middle East Peace testified Wednesday to the committee that "the nightmare" being endured by the Syrian people may be far from over but will end.
"Our job is to try to ensure it ends sooner rather than later and with as little damage to the institutions of the Syrian state and the unity and the well-being of the Syrian people as possible," Frederic C. Hof said. Referring to Syria's president, he added, "Bashar al-Assad and his inner circle can best contribute to the welfare of their countrymen by stepping aside now, without delay."
Meanwhile, Syria was to on the agenda as a European Union-Russia summit got under way Wednesday in Brussels, Belgium. On Tuesday, the U.S. State Department singled out Russia for blocking a United Nations response to the situation in Syria. In October, Russia -- a longtime ally of al-Assad -- was one of four Security Council members voting against a resolution condemning Syria.
"We are again calling on our partners on the Security Council to be willing to take action and speak out for the innocents in Syria who are suffering at the hands of the regime, including Russia," State Department spokeswoman Victoria Nuland said Tuesday. "And frankly, we think it is past time for the U.N. Security Council to speak up."
She warned, however, of any shift to armed response by opponents of the regime.
"The view of the vast majority of Syrians, and particularly those in opposition -- a view that we share -- is that further militarizing the situation in Syria is not in the interests of anyone and could threaten to rip the fiber of the country apart," she said. "This is exactly what the regime wants. The regime wants an armed conflict because that is what they understand."
Russia is a major partner for the EU, foreign policy chief Catherine Ashton noted in a speech in Brussels on Tuesday.
Russian Foreign Minister "Sergey Lavrov and I meet regularly and try to build common approaches to the most pressing international issues," she said. "Generally we succeed, but in some cases our positions differ, like ... on Syria, which no doubt will be raised at the summit."
Lavrov on Tuesday accused the Syrian opposition of trying to provoke a humanitarian crisis to justify foreign military intervention. But Lavrov also said Syria should accept Arab League proposals for ending the violence and allow foreign observers into the country.
More than 5,000 people have died in Syria, U.N. Commissioner for Human Rights Navi Pillay said Monday. The Syrian ambassador to the United Nations dismissed the figure as "incredible."
But Pillay, who briefed the Security Council and spoke to reporters afterward, called the situation "intolerable" and said she is "appalled by the constant stream of grave violations that have taken place since the first protests in Syria in March."
"That death toll does not include security and military forces, but hundreds of those are believed to have died as well," she said.
Opposition figures said the Syrian government had warned people in Homs to stop anti-government protests, hand in their weapons and surrender defecting military members by Monday night or face attack by government forces. The government did not acknowledge a deadline in state-run media, and it remained unclear what had happened in the city.
CNN's Mick Krever contributed to this report.