BEIRUT -- Syrian rebels led by al Qaidas regional affiliates killed and kidnapped hundreds of civilians during an offensive in coastal Syria in early August, one of the worst atrocities ever blamed on forces fighting to topple President Bashar Assad, according to a report to be released Friday by an international human rights group.
Investigators for Human Rights Watch said the killings were carried out Aug. 4 in villages in Syrias Latakia province, which is Assads ancestral home. Most of the victims were Alawites, members of the Muslim sect to which Assad and much of Syrias elite belong.
As many as 190 civilians in 14 villages were summarily executed during the onslaught, the group said. Another 200 were kidnapped and remain missing. The death toll may be even higher, the group said. Investigators who visited the scene said a doctor at one hospital reported receiving 205 bodies, some of which had been decapitated and several of which were bound.
Human Rights Watch didnt directly implicate the U.S.-backed Supreme Military Command or its Free Syrian Army in the atrocities. But it noted that defected Syrian army Gen. Salim Idriss, who heads the Supreme Military Command, had issued statements that indicated his fighters were taking part in the offensive. The group said those statements should be examined to determine what role his fighters might have played in the killings and kidnappings of civilians.
Human Rights Watch also called on Idriss and the Syrian Opposition Coalition, a U.S.-backed civilian anti-Assad umbrella group, to cease cooperation and coordination with and support to armed groups credibly found to perpetrate systematic abuses against the civilian population; and in particular Ahrar al Sham, the Islamic State of Iraq and Sham, Jabhat al Nusra, Jaish al Muhajireen wal-Ansar and Suquor al Izz.
Those five groups were the key fundraisers, organizers, planners and executors of the Latakia campaign, the report says. The Islamic State, Nusra and Jaish are al Qaida affiliates; Ahrar al Sham and Suquor al Izz are conservative Islamist groups.
The report also singles out Turkey, calling on it to do more to stop foreign Islamist fighters from crossing into Syria.
Given that most foreign fighters in these groups reportedly gain access to Syria via Turkey, it says, Turkey should increase border patrols (and) restrict entry of fighters and arm flows to groups credibly found to be implicated in systematic human rights violations.
It says Turkey should investigate and prosecute those in Turkey suspected of committing, being complicit in or having command responsibility for international crimes and that the United Nations Security Council should take steps to make sure that Turkey does.
There was no immediate comment from Idriss or the Syrian Opposition Coalition. The Turkish Embassy in Washington didnt respond to emailed questions.
In recent weeks, Free Syrian Army rebels and fighters from the Islamic State have battled each other across northern and eastern Syria. But at the time of the Latakia assault, the two groups cooperated closely.
On Aug. 6, the Syrian Opposition Coalition praised the role of the Islamic State and Nusra in the capture of a Syrian government base in Idlib province. On Aug 10, Idriss released a statement that said his fighters were participating in the Latakia offensive and that they were under orders to protect civilians on both sides of the conflict.
Observers said it would be difficult for SMC-affiliated to break completely with the five organizations, whose troops make up anywhere from 25 to 40 percent of the rebel fighters but are not part of the U.S.-supported organization.
Dan Layman, a spokesman for the U.S.-based Syrian Support Group, a fundraising organization for the armed opposition, said the Supreme Military Command punished any affiliated group that committed human rights violations by cutting off supplies.
But he said it wouldnt make sense for U.S.-backed local rebel commanders to cease all joint operations with Islamist hard-liners when they were on the same side of a brutal civil war and needed all the help they could get, especially since aid from the United States and other Western nations had been slow to arrive.
You dont get something for nothing, Layman said. You cant kill people with your transitional justice, and you cant eat your Human Rights Watch report.
The report describes the Latakia campaign as a coordinated offensive that comprised fighters from 20 rebel groups and attacks on 14 population centers. The systematic way in which the violence unfolded makes it unlikely that the human rights violations were perpetrated only by rogue elements, the report says.
The offensive began in the early morning hours in the town of Barouda, the report says, when opposition forces overran a government position and two neighboring bases, killing approximately 30 soldiers and wounding many more.
Rebel fighters then entered the villages of Barouda, Nbeiteh, al Hamboushieh, Blouta, Abu Makkeh, Beyt Shakouhi, Aramo, Bremseh, Esterbeh, Obeen and Kharata, the report says, and eventually, in subsequent days, the villages of Qalah, Talla and Kafraya.
According to the report, the rebel fighters gunned down civilians as they tried to flee. In some cases, they entered homes and killed the people they found inside.
The evidence gathered by Human Rights Watch indicates that all those unlawfully killed were civilian noncombatants, the report says. There is no evidence that they could have posed, or could have been perceived to pose, any threat to the fighters.
It says some of the rebel opposition abuses had clear sectarian motivations. It says that in Barouda, rebels intentionally damaged an Alawite maqam a site where a religious figure is buried and appear to have intentionally damaged and dug up the grave of the religious figure buried there as well.
Human Rights Watch said its report relied on testimony from survivors, medical personnel, a non-Islamist pro-rebel activist and Western diplomatic officials familiar with movements of rebel groups through the Turkish border to support its stark conclusion that the rebels committed a war crime.
Eight survivors and witnesses described how opposition forces executed residents and opened fire on civilians, sometimes killing or attempting to kill entire families who were either in their homes unarmed or fleeing from the attack, and at other times killing adult male family members, and holding the female relatives and children hostage, the report explains.
The report identifies the commanders of some of the groups by name and urges that the case be referred to the International Criminal Court in The Hague, Netherlands, where war crimes are prosecuted.
Experts on radical Islamist movements said the report was unlikely to hurt the groups with their supporters.
They view Alawites as not Muslims, and therefore they are legitimate targets to kill, said Aaron Zelin, a fellow with the Washington Institute for Near East Policy. Whereas when it comes to Sunnis, they are a lot more careful with target selection, only focusing on those that have collaborated with the Assad regime or broken the law in areas that are liberated based on their strict interpretation of Islamic law.
Hannah Allam contributed to this report from Washington.
UPDATE:This story has been changed to better reflect where in the structure of the Free Syrian Army coordination with Islamist groups take place. The coordination is primarily at the local level, not at the overall command level.