BEIRUT -- Fresh violence erupted Friday in the besieged Syrian city of Homs, a day after armed forces loyal to President Bashar Assad barraged residential buildings with mortars and machine-gun fire, killing at least 30 people including a family of women and children, activists said Friday.
The violence began Thursday, but important details were only emerging a day later. Video posted online by activists showed the bodies of five small children, five women of varying ages and a man, all bloodied and piled on beds in what appeared to be an apartment after a building was hit in the Karm el-Zaytoun neighborhood of the city. A narrator said an entire family had been "slaughtered."
The video could not be independently verified.
On Friday, heavy gunfire again hammered the city, which has seen some of the heaviest violence of the 10-month-old uprising against Assad's rule. Activists said at least 11 people were killed across the country, four of them in Homs.
Elsewhere, a car bomb exploded Friday at a checkpoint outside the northern city of Idlib, the British-based Syrian Observatory for Human Rights said, citing witnesses on the ground. The number of casualties was not immediately clear.
A "fierce military campaign" was also under way in the Hamadiyeh district of Hama since the early hours of Friday, according to the Observatory and other activists. They said the sound of heavy machine-gun fire and loud explosions reverberated across the area.
The head of Arab League observers in Syria said in a statement that violence in the country has spiked over the past few days. Sudanese Gen. Mohammed Ahmed al-Dabi said the cities of Homs, Hama and Idlib have all witnessed a "very high escalation" in violence since Tuesday.
In an attempt to stop the bloodshed in Syria, the U.N. Security Council was to hold a closed-door meeting Friday to discuss the crisis, a step toward a possible resolution against the Damascus regime, diplomats said. The U.N. says at least 5,400 people have been killed in the government crackdown since March, and the turmoil has intensified as dissident soldiers have joined the ranks of the anti-Assad protesters and carried out attacks on regime forces.
Details of Thursday's wave of killings in Homs were emerging from an array of residents and activists on Friday, though they said they were having difficulty because of continuing gunfire.
"There has been a terrifying massacre," Rami Abdul-Rahman, director of the Syrian Observatory for Human Rights, told the AP on Friday, calling for an independent investigation.
Thursday started with a spate of sectarian kidnappings and killings between the city's population of Sunnis and Allawites, a Shiite sect to which Assad belongs and which is the backbone of his regime, said Mohammad Saleh, a centrist opposition figure and resident of Homs.
There was also a string of attacks by gunmen on army checkpoints, Saleh said. Checkpoints are a frequent target of dissident troops who have joined the opposition.
The violence culminated with the evening killing of the family, Saleh said, adding that the full details of what happened were not yet clear.
The Observatory said 29 people were killed, including eight children, when a building came under heavy mortar and machine gun fire. Some residents spoke of another massacre that took place when shabiha -- armed regime loyalists -- stormed the district, slaughtering residents in an apartment, including children.
"It's racial cleansing," said one Sunni resident of Karm el-Zaytoun, speaking on condition of anonymity for fear of reprisal. "They are killing people because of their sect," he said.
Some residents said kidnappers were holding Alawites in the building hit by mortars and gunfire in Karm el-Zaytoun, but the reports could not be confirmed.
Thursday's death toll in Homs was at least 35, said the Observatory and the Local Coordination Committees, an umbrella group of activists. Both groups cite a network of activists on the ground in Syria for their death tolls. The reports could not be independently confirmed.
Syria tightly controls access to trouble spots and generally allows journalists to report only on escorted trips, which slows the flow of information.
The Syrian uprising began last March with largely peaceful anti-government protests, but it has grown increasingly violent in recent months.
It has also seen outbreaks of bloody tit-for-tat sectarian killings. Syria has a volatile religious divide, making civil unrest one of the most dire scenarios. The Assad regime and the leadership of its military and security forces are dominated by the Alawite minority, but the country is overwhelmingly Sunni Muslim.
Also Friday, Iran's official IRNA news agency said gunmen in Syria have kidnapped 11 Iranian pilgrims traveling by road from Turkey to Damascus.
Iranian pilgrims routinely visit Syria -- Iran's closest ally in the Arab world -- to pay homage to Shiite holy shrines. Last month, 7 Iranian engineers building a power plant in central Syria were kidnapped. They have not yet been released.
The Free Syrian Army -- a group of army defectors -- released a video on its Facebook page claiming responsibility for the kidnapping and saying the Iranians were taking part in the suppression of the Syrian people. The leader of the group could not be reached for comment.
In Switzerland, U.N. rights chief Navi Pillay said the "fragmentation within the country" was making it harder for the U.N. to update its death toll in Syria.
"Some areas are completely closed, such as parts of Homs, we are unable to verify much of the information that's coming to us. We are watching the figures, working closely with civil society organizations, and sifting through all the information that's coming to us," she said at the Davos Forum.
But she expressed "great concern that the killings are continuing and in my view it's the authorities who are killing civilians, and so it would all stop if an order comes from the top to stop the killings."
Assad's regime claims terrorists acting out a foreign conspiracy are behind the uprising, not protesters seeking change, and that thousands of security forces have been killed.
International pressure on Damascus to end the bloodshed so far has produced few results.
The Arab League has sent observers to the country, but the mission has been widely criticized for failing to stop the violence. Gulf states led by Saudi Arabia pulled out of the mission Tuesday, asking the Security Council to intervene because the Syrian government has not halted its crackdown.
The U.N. Security Council has been unable to agree on a resolution since violence began in March because of strong opposition from Russia and China.
A senior Russian diplomat said Moscow will oppose a new U.N. draft resolution on Syria because it fails to take the Kremlin's concerns into account.
Deputy Foreign Minister Gennady Gatilov was quoted by the ITAR-Tass news agency as saying Friday that the draft worked out by the West and some Arab states fails to exclude the possibility of outside military interference.
In Cairo, Arab League chief Nabil Elaraby told reporters that he and the prime minister of Qatar would leave for New York on Saturday to seek U.N. support for the latest Arab plan to end Syria's crisis. The plans calls for a two-month transition to a unity government, with Assad giving his vice president full powers to work with the proposed government.
Syria has rejected the proposal, saying it violates its sovereignty.
Bassma Kodmani, a spokeswoman for the opposition Syrian National Council, said the Arab initiative was a move in the right direction and urged Security Council members to shoulder their "moral and political responsibilities" in bringing emergency assistance to the Syrian people.