BEIRUT—A new video appears to show Syrian rebels killing a group of captured soldiers, spraying them with bullets as they lay on the ground. Human rights groups on Friday warned that the gunmen may have committed a war crime.

Syrian jets pound rebel strongholds

The video raises concerns over brutality among some rebels just ahead of a major conference this weekend in Qatar at which the United States is trying to unify the opposition under a new leadership. Washington and its allies have been hesitant to give stronger support to the rebellion in part because of worries over its multiple divisions and lack of organization.

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The killings took place Thursday during an assault by rebels on the northern town of Saraqeb, the scene of heavy fighting in past weeks between rebels and forces of President Bashar Assad's regime, according to an anti-regime activist organization, the Syrian Observatory for Human Rights.

Rebels are now in full control of Saraqeb after regime troops pulled back during Thursday's fighting, the Observatory said. That gives the rebels a strategic point on the main highway linking Syria's largest city Aleppo — which rebels have been trying to capture for months — with the regime stronghold of Latakia on the Mediterranean coast.

Reports of serious human rights abuses by elements within the armed opposition have been on the rise, badly damaging the rebels' claims of moral high ground in the civil war and fueling concerns that they are capable of a brutality matching that of the regime they are seeking to topple.

The issue is complicated by the fragmented nature of the rebellion. Even rebel units nominally under the umbrella Free Syrian Army group operate independently, and as the 19-month-old conflict drags on, criminals, foreign Islamic militants and other renegades have joined in the fight against Assad.

In early August, a video showed several bloodied prisoners being led into a noisy outdoor crowd in the northern city of Aleppo and placed against a wall before gunmen open fire and shoot them to death. According to activists, the slain prisoners were members of the powerful Barri clan, which has long had close ties to the Syrian government.

That video sparked international condemnation, including a rare rebuke of rebel tactics from the Obama administration.

There have been other videos of individual summary execution-style killings. Throughout the 19-month-old conflict, there have been other reports of brutal sectarian killings by opposition gunmen — including, according to one report by a Shiite watchgroup, the beheading of Iraqi Shiites living in Syria. At the same time, there have been repeated reports of massacres by regime forces and by the pro-government fighters known as shabiha.

Human rights groups said Friday they were trying to confirm the authenticity of the new video. The footage was consistent with other Associated Press reporting in the area. The video is dated Thursday, a day when the Observatory reported heavy attacks by rebels on regime checkpoints at Saraqeb.

The amateur video, posted on YouTube, shows a crowd of gunmen, apparently rebels, in what appears to be a building under construction.

They surround a group of captured men on the ground, some on their bellies as if ordered to lie down, others sprawled as if wounded. Some of the men are in Syrian military uniforms. “These are Assad's dogs,” one of the gunmen is heard saying of the captured men.

The gunmen kick and beat some of the men, who appear terrified as one gunman shouts, “Damn you.” The exact number of soldiers in the video is not clear, but there appear to be around 10 of them.

Seconds later, amid the screams of those captured, gunfire erupts for around 35 seconds and the men on the floor are seen shaking and twitching, apparently from being struck by bullets. The spray of bullets raises a cloud of dust from the ground.

The video is titled “prisoners and dead from the regime military at the Hmeisho checkpoint.” On Thursday, the Observatory had reported 12 soldiers killed at Hmeisho, outside Saraqeb, one of three major rebel attacks on military checkpoints in the area.

Thursday saw heavy casualties for the military around the country, with 83 soldiers killed in attacks by rebels and clashes, the Observatory said. Half of those were killed in Idlib province, where Saraqeb is located.

Ausama Monajed, a Britain-based member of the Syrian National Council opposition group, called for an investigation of the incident. He said the unit responsible for the apparent killing of unarmed regime soldiers must be tracked down and tried.

Monajed alleged that the regime has created “fake” rebel units in the past to commit atrocities and tarnish the rebels' reputation.

“We are not saying this is the case,” he said. “We need to identify the unit.”

He said atrocities committed by rebels are relatively rare compared to what he said was the “massive genocide by the regime.”

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Rami Abdul-Rahman, who heads the Observatory, estimated that around 20 people were killed in the portrayed summary executions, but the number could not be accurately verified.

The identity or affiliation of the fighters on video was unknown. But Abdul-Rahman and other activists said several brigades are known to operate in the area, including Jabhat al-Nusra, a shadowy Islamic militant group with an al-Qaida-style ideology.

At least 36,000 people have been killed since the uprising against Assad began in March 2011 and then transformed into an outright civil war, according to anti-regime activists. Thousands of people have been killed over the past few months, including more than 500 last week during a four-day internationally-brokered cease-fire that collapsed shortly after it went into effect.

On Wednesday, the Obama administration said it would push for a major shakeup in the opposition leadership so that it better represents the fighters risking their lives on the frontlines. The opposition's political leadership, mostly in exile, has been criticized as increasingly irrelevant and out of touch.

U.S. Secretary of State Hillary Rodham Clinton said the administration was suggesting names and organizations that should feature prominently in any new rebel leadership that is to emerge from a four-day conference starting Sunday in Doha, the capital of Qatar. She said the new leadership should better represent those dying on the front line, a reference to the rebels.

London-based Amnesty International and the U.N. High Commissioner for Human Rights both said they were trying to confirm the video's authenticity and determine the identity of the gunmen.

“This shocking footage depicts a potential war crime in progress, and demonstrates an utter disregard for international humanitarian law by the armed group in question,” said Ann Harrison, Amnesty's deputy Middle East and North Africa program director.

UNHCHR spokesman, Rupert Colville, said “the allegations are that these were soldiers who were no longer combatants and therefore, at this point, it looks very like a war crime.”

“Unfortunately this could be the latest in a string of documented summary executions by opposition factions as well as by government forces and groups affiliated with them, such as the (pro-government) shabiha” militia, he told reporters in Geneva.

“The people committing these crimes should be under no illusion that they will escape accountability, because there is a lot of accumulated evidence, perhaps including this video,” he said.

Fadi al-Yassin, an activist in Idlib province that includes Saraqeb, told The Associated Press that rebels captured three checkpoints around the town on Thursday after heavy fighting. Al-Yassin said he did not see the video.

“Some soldiers surrendered, while others fought,” he said. “It could be in individual act. There are rebels who lost loved ones or suffered at the hands of the regime.”

Al-Yassin said captured soldiers are usually well-treated by rebels who get information from them then refer them to makeshift tribunals. Those who are innocent are set free, he said.

Also Friday state TV reported that two bombs went off minutes apart in the Damascus neighbourhood of Zahira al-Jadida wounding 16 people.

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