Violence surged in Syria on Friday, with government forces using heavy artillery to bombard several towns, while the United Nations debated a resolution on ways to end the bloodshed, intensifying the diplomatic pressure on Damascus.

According to activists, a military crackdown that ebbed when an Arab League monitoring team began its work in the country more than a month ago resumed this week with heightened force.

“In some areas, the shelling has not stopped for three days in a row,” said an activist in the central city of Homs who uses the name Hadi al-Homsi. “The regime is now waging full-scale war against the people.” He described what he called a “massacre” in the district of Karm al-Zeitoun, a focal point of government military operations in the city.

Although movement between Homs neighborhoods is limited, residents participated in demonstrations after prayers, Homsi said, joining protesters elsewhere in chants hailing the “Friday of the right to self-defense.”

That designation — the latest given to weekly demonstrations that have rocked Syria during its 10-month-old uprising against the government of President Bashar al-Assad — is ominous, said Rami Abdulrahman of the London-based Syrian Observatory for Human Rights. He said he was increasingly afraid that the country is in a state of civil war.

According to Abdulrahman, 62 people were killed across Syria on Thursday, including 33 in Homs, and at least 60 more, including 47 civilians, on Friday. It was not possible to confirm the death toll because of tight restrictions imposed on journalists, but U.N. human rights chief Navi Pillay has said that more than 5,400 people — including civilians, army defectors and security troops executed for refusing to shoot civilians — have died since the uprising began in March.

Asked whether those killed in Homs were civilians or armed opposition members, Abdulrahman said the difference between the two was becoming ever more vague. He added that a growing number of soldiers were defecting to join a loose opposition group known as the Free Syrian Army.

The head of the Arab League observer mission, Mohammed Ahmed al-Dabi, issued a statement Friday condemning the latest surge in violence and saying that the circumstances were not conducive to the negotiations the Arab group called for Sunday in a wide-ranging proposal.

At a closed-door meeting in New York on Friday, the U.N. Security Council debated a draft resolution — introduced by Morocco on behalf of a group of European and Arab countries — that would condemn Syrian repression of protesters, endorse the Arab League’s proposal that Assad step down, and call on all countries to adopt financial and travel sanctions already introduced by the Arab League.

The developments in the Security Council underscore Syria’s deepening isolation at the United Nations. In recent months, the country has been the subject of numerous resolutions in the Human Rights Council and the General Assembly condemning its conduct.

Arab League Secretary General Nabil Elaraby and Qatari Prime Minister Hamad Bin Jasim al-Thani, who leads the Arab League committee overseeing its Syria policy, are expected to brief a ministerial-level Security Council meeting early next week ahead of an as-yet-unscheduled vote on the resolution.

Russia, a close ally of Syria and permanent member of the Security Council, has warned that it will block any U.N. measure that requires Assad to step aside. Speaking to reporters after Friday’s meeting, Moscow’s U.N. ambassador, Vitaly Churkin, said the draft measure did not provide “a basis on which we can agree.” Russia, which has been pressing its own resolution, will continue to “engage” on the matter, he said.

Syria’s U.N. ambassador, Bashar al-Jaafari, said Western powers think Syria is “still under their hegemony, and they deal with us as if we are a former colony, that we should subjugate ourselves to their will.” He added: “They are wrong, and they will be disappointed.”

Reverberations from the unrest in Syria have been increasingly felt across the Middle East. In Cairo on Friday, about 200 Syrian protesters stormed the Syrian Embassy, breaking windows and doors and ransacking offices. The Syrian ambassador, Yousef Ahmed, blamed Egypt’s security forces for failing to prevent the attack.

Also Friday, the Free Syrian Army appeared to score a strategic victory over the Iranian government, which backs Assad, when it released a video showing a group of Iranian hostages in Syria. The video, posted online, shows five men displaying Iranian identity cards, two of them military, while Syrian fighters urge the Assad government to admit that members of Iran’s Revolutionary Guard Corps are operating in the country.

It was not possible to verify the provenance of the footage.

Reached by telephone, Col. Malik al-Kurdi of the Free Syrian Army said the group had invited the Syrian government to negotiate the hostages’ release, calling for an end to shelling, a withdrawal of tanks and a prisoner release.

Lynch reported from New York. Correspondent Leila Fadel in Cairo contributed to this report.