CAIRO, Aug 14 (Aswat Masriya) - International watchdog Human Rights Watch (HRW) called on Egypt’s parliament to pass a transitional justice law establishing a new, impartial investigation into the "mass killing of protesters" in the 2013 Rabaa sit-in.

Sunday marks the third anniversary of the dispersal of the sit-in held at the Rabaa Al-Adaweya Square in Cairo in late June 2013.  The encampment, organised in solidarity with and to show support for president Mohamed Mursi and his administration, was maintained for weeks before security forces dispersed it on Aug. 14, 2013.

“If President Abdel Fattah al-Sisi’s government hopes to have any credibility with the thousands of Egyptians who have suffered over the past three years, it should ensure a serious accounting for these grave crimes,” Middle East and North Africa director at HRW Sarah Leah Whitson said.

“The mass killings of August 14, 2013, remain a dark stain on Egypt’s record that no amount of spin from the government or its allies will ever wash away.”

The constitution requires parliament to pass a transitional justice law during its first session, which will probably end in October. The law is expected to ensure revealing the truth, accountability, proposing frameworks for national reconciliation, and compensating victims, in accordance with international standards. 

HRW said in a report issued on Sunday that it documented six instances in which security forces unlawfully killed protesters, leaving at least 1,185 people dead between Morsy’s ouster on July 3, 2013, and August 16, 2013. 

The number of people who were killed during the dispersal remains contested, with varying death tolls claimed by different sources.

The state's Forensic Authority said in late 2013 that 627 were killed in the dispersal, while the state's National Council for Human Right said in March 2014 that the death toll was 632, including eight security personnel. 

But Wiki Thawra, a website that describes itself as a "statistical database of the Egyptian revolution," said 932 were killed in the incident. 

HRW has constantly accused the Egyptian government of cracking down on activists and silencing opposition, while Egyptian authorities have repeatedly described the watchdog organisation as biased, saying they lack professionalism and ignore martyrs from the security forces side.