For those looking at Syria’s four-year-long conflict from the outside, the slaughter has appeared to have little or no pattern, a barbaric struggle in which all are equally guilty. But a new survey of blood-curdling sectarian massacres perpetrated in Syria since the start of the civil war provides a very clear picture of the ultimate villain behind the carnage.

According to the survey by the Syrian Network for Human Rights, there have been 56 major massacres displaying obvious sectarian or ethnic cleansing traits. Of these 49 were carried out by Syrian government forces or local and foreign militia allies of President Bashar al-Assad, making a mockery of the Syrian leader’s frequent claim to foreign broadcasters that his soldiers would never harm their own people deliberately as a matter of policy.

In fact, three days before Assad sat down with the BBC for an especially chilling interview last February and lamented how war, alas, causes casualties, government-aligned militiamen stormed the As-Sabil neighborhood in the Syrian city of Homs and slaughtered three Sunni families, including four children and five women.

The non-profit SNHR, which is based and registered in the U.K., was founded in 2011 after the outbreak of the uprising against Assad. The UN has used SNHR’s statistics in reports analyzing the conflict’s victims and it is widely considered among the most reliable NGO’s when documenting death tolls.

In recent months Assad, seeking to gain political advantage, has done much to craft a narrative depicting himself as the West’s best ally in the fight against Islamic extremism in Syria and Iraq. That storyline obscures, of course, the fact that from the start the Syrian leader helped to encourage extremists by releasing jihadi prisoners from jails and then, for months, avoided targeting ISIS in eastern Syria. It obfuscates as well the essentially sectarian massacres carried out over the past four years by Assad’s soldiers and the militias set up by Iranian advisers to work with them.

The Syrian Network for Human Rights focuses in its survey on “massacres that involve certain patterns and practices where the aggressor forces don’t only kill victims by shooting them, but carry out other criminal acts such as slaughtering whole families, including children and women, burning bodies, deforming bodies, sexual crimes, looting and burning homes.” All of these crimes possess sectarian traits with the victims targeted being mainly Sunni Muslim.

“In most of the cases, the ruling authorities’ militias loot [a home], destroy it, or occupy it… the purpose of these acts is to prevent its Sunni residents from coming back,” the survey’s authors note. They also argue that the frequency and scale of the massacres make it impossible for the Assad government not to be aware of them. “The Syrian authorities have never held anyone accountable for these crimes,” the authors say.

From March 2011 until June 2013 all the sectarian massacres were carried out by government forces or their local and foreign militia allies. SHNR argues the Assad regime was hoping for propaganda purposes to provoke its foes to resort to similar sectarian and ethnic-based violence. If that was indeed its aim, then it was achieved.

Since mid-2013, SHNR notes ISIS or Daesh (which calls itself the Islamic State), al Qaeda affiliate Jabhat al-Nusra, Kurdish YPG forces and some other armed opponents of Assad have conducted sectarian or ethnic-based massacres. SNHR has documented four massacres involving miscellaneous rebel fighters, ISIS and al-Nusra in which 178 civilians were killed including 26 children and 72 women. Another three sectarian massacres that left 58 dead victims can be blamed on ISIS alone, and the researchers accuse the YPG of conducting three ethnic-cleansing massacres that left nearly 100 dead. YPG officials have denied the accusation that any of their fighters have been involved in ethnic-based massacres.

The survey doesn’t include the mass execution by ISIS of up to 250 Syrian soldiers last August in Raqqa—a slaughter that bolstered the Islamic extremists’ reputation as the most brutal terrorist outfit in the World. The SHNR survey keeps within technical parameters, emphasizing the civilian toll and including only massacres where people have been targeted either because of their membership of a religious sect or ethnicity.

One of the early Assad massacres included in the survey came in the az-Zahraa neighborhood of Homs on 6 December 2011 when local militias made up of members of Assad’s minority Alawi sect, an offshoot of Shia Islam, gathered 19 residents in the main square and then proceeded to torture them before gunning them down.

Homs, strategically located near the Lebanese border, has had more than its fair share of Assad-perpetrated massacres. In the spring of 2012 there were a series in three districts, including the Az-Zaitoun neighborhood, involving government forces and members of the notorious Shabiha militia, the ultra-loyal Alawi enforcers of the regime. First came a siege and then homes were raided by the assailants who raped and killed as they went. Dead bodies were burned, corpses were mutilated and SNHR documented the killing of 224 victims including 44 children and 48 women.

The Daily Beast interviewed some months later a 38-year-old woman who was a survivor of the massacre. She had been shot in the hand, seen her husband’s first wife slain and a neighbor raped. She and her three daughters only escaped because one militiaman took pity on her. “They raped teenage girls,” Saima told me almost in a whisper, claiming that the day after the massacre she saw naked girls in the hospital piled up, dead and bearing obvious signs of sexual abuse.

And the massacres have continued. One of the worst was in the town of Jadedat al-Fadl in the countryside outside the Syrian capital of Damascus. It took place over eight days in April 2013 when government soldiers and local militias besieged the town, cut off power and communications and then shelled the al-Mwali neighborhood. Then the fighters moved in, gunning down their victims and even stoning some of them to death. Entire families were slaughtered. SNHR documented by name 191 victims; 17 of whom were rebels, and 174 civilians including nine children and eight women. Some opposition activists have put the death toll as high as 500.

A month later Hezbollah, the Iranian-nurtured Lebanese Shia militia, was also implicated in a sectarian massacre joining Syrian army regulars and local militias—the Lebanese fighters had helped to train them—to besiege the Sunni districts of the city of Baniyas and the Sunni village of Bayda. Again, entire families were slaughtered. Residents found children’s legs hacked off. SNHR documented by name 459 civilian victims, including 92 children and 71 women. According to a subsequent UN report between 300 and 450 people were slaughtered. The killings were supposedly in retaliation for a rebel attack near Baniyas that left half a dozen Syrian government soldiers dead.

As the massacres continue, of course, the sectarian nature of the conflict increases, reducing the chances of a reconciliation, or of any kind of peace being forged between Syria’s Sunni majority and its Alawi minority.