This post has been updated. See below for details.
BEIRUT -- Allegations of a fresh massacre in Syria surfaced Friday as activists said security forces shot and killed 12 factory workers returning home from work in a bus near the town of Qusayr in the restive province of Homs.
The men were traveling home from their jobs in a state-run fertilizer factory on Thursday afternoon when the bus was stopped at a military checkpoint on the outskirts the town, Salim Kabbani of the Syrian opposition activist network Local Coordination Committees told The Times via telephone.
The men were summarily executed there by gunshots, Kabbani said, and their bodies were dumped in a field on the outskirts of Qusayr. None of the men were known activists, and all were buried Thursday evening, Kabbani said.
But the pro-government Facebook page, the Homs News Network, put the blame on the killings on the rebel Free Syrian Army, saying the workers were killed because they were state employees, the Associated Press reported.
The killings again raised fears that Syria was plunging into a cycle of tit-for-tat sectarian massacres and a possible civil war, fears voiced by this week by Secretary of State Hillary Rodham Clinton and Susan Rice, U.S. ambassador to the United Nations.
The latest reported massacre remained uncorroborated by U.N. monitors inside Syria, but video was posted on the Internet purporting to show the bodies of at least nine men, wrapped in white sheets, laid out inside a building.
[Updated 10:56 a.m., June 1: The U.N. monitors’ spokesperson said Friday that opposition and government groups confirmed that at least 12 people were killed in the Qusayr area, but the circumstances surrounding the killings are contested by both sides.]
The images and other online video of men with grievous wounds said to be victims of the bus massacre could not be independently confirmed.
The incident would be the third massacre reported from Syria in the last week -- including the execution-style murder of 13 men near the eastern city of Deir Elzour and the house-to-house killings of 108 people, mostly children and women, in the township of Houla in Homs province.
The Houla massacre has galvanized international public opinion against the Syrian government, but authorities say anti-government "armed groups" carried out the killings, targeting loyalist families, including the family of a member of parliament.
Brig. Gen. Qassem Jamal Suleiman, chief of the Syrian government's committee probing the Houla massacre, alleged that gunmen gathered inside the town following Friday prayers, along with 600 to 800 fighters from other areas, and began the "onslaught simultaneously," Syria's official SANA news agency reported. Suleiman said the goal of the "armed attack" was to bring the area under control of the "armed groups."
Syrian activists, however, blame the gruesome killings in Houla on the shadowy pro-government paramilitary militia known as Shabiha, from the Arabic word for ghosts. Activists of the Syrian Revolution 2011 Facebook page -- a driving machine behind anti-government rallies -- are urging Syrians to take to the streets Friday in protest for the "Children of Houla."
Activists also called on members of the capital's merchant class who shuttered their shops in Old Damascus earlier this week in an apparent protest of the Houla killings to continue their strike. Merchants have been considered a key sector of support for the embattled government of President Bashar Assad.
"These strikes represent a major blow to the now-defunct regime, which had been counting on the masses to maintain their silence," the Local Coordination Committees said Friday in a statement."But the train of history is on its way. And this train must stop at the station in central Damascus -– a station that may represent the beginning of the end."
The latest massacre scenario -- with the factory workers said to have been pulled off a bus -- matches at least one earlier mass killing in the Homs area. It was unclear Friday if a sectarian motive was involved, but other such cases have reportedly featured gunmen at roadblocks selecting motorists and bus passengers for execution based on their sect.
Homs, like all of Syria, is mostly made up of Sunni Muslims, but the province also has significant minorities of minority Christians and Alawites, the latter an offshoot of Shiite Islam. Assad and much of the leadership of his security and intelligence apparatus come from the Alawite sect.
-- Alexandra Sandels and Patrick J. McDonnell