According to preliminary reports, the remains of around thirty (30) government soldiers and non-combatants have been unearthed so far, more corpses may yet be found has the excavation continues.
Specifically, the makeshift burial site was found just south of Douma city’s al-Jalaa gardens area. Jaish al-Islam
...Liwa al-Islam (Brigade of Islam) was established by Zahran Alloush, the son of Saudi-based religious scholar Abdullah Mohammed Alloush, after Syrian authorities released him from prison in mid-2011 where he had been serving time for his Salafist activism. The group claimed responsibility for carrying out the July 2012 Damascus bombing that killed Defense Minister Dawoud Rajiha, Deputy Defense Minister Asef Shawkat, and Assistant Vice President Hassan Turkmani. It was a driving force behind actions in the Damascus region. It cooperated and conducted joint operations with al-Nusra. In Sptember 2013 Saudi Arabia engineered Liwa al-Islam's merger with fifty other more or less Salafist groups as a counterweight to al-Nusra, which the Learned Elders of Islam considered was growing too powereful...turbans are believed to be the perpetrators of the massacre.
Al-Masdar News journalist Ibrahim Joudeh says that the mass grave found in Douma is possibly just one of tens that exist throughout the area, given that Jaish al-Islam is known to have captured and executed hundreds of Syrian troops and civilians over the last five years.