CAIRO, Aug 14 (Reuters) – Rights groups called on Monday for accountability over the deaths of hundreds of people killed in a single day 10 years ago when Egyptian security forces dispersed a protest against the ouster of the country’s first democratically elected president.

The clearing of the Rabaa al-Adawiya sit-in in Cairo on Aug.14, 2013 marked the escalation of a crackdown against supporters of overthrown Muslim Brotherhood leader Mohamed Mursi. The crackdown later expanded to include activists and politicians from across the political spectrum.

Rights groups say more than 800 people were killed as security forces stormed Rabaa al-Adawiya, one of two squares in the capital where protesters had been camped out for weeks.

Official accounts of the dispersal, including in a state-backed TV series, have portrayed security forces responding to attacks by armed protesters after appealing to them to leave peacefully.

Hundreds of those accused of involvement in the protest were convicted in a mass trial in 2018, many receiving death sentences or long prison terms.

“Egyptian authorities have failed for a decade to hold anyone accountable for the largest mass killing in Egypt’s modern history,” Human Rights Watch said in a statement.

Amnesty International said: “States with influence on Egypt must echo the demands of survivors, victims’ families and human rights defenders for truth, justice and reparation.”

The Egyptian Initiative for Personal Rights (EIPR), a leading independent group, said in a report that it had obtained information from an official investigation of which only the executive summary was made public, showing that authorities had considered less lethal ways of dispersing the sit-in.

The state information service did not respond to a request for comment on the report.

Supporters of Abdel Fattah al-Sisi, who led Mursi’s ouster as army chief and became president in 2014, say security measures taken at the time were needed to stabilise Egypt.

Official figures recorded the deaths of 618 civilians and nine security personnel at the Rabaa dispersal, though this count only included bodies received by the state forensic authority, EIPR said.

“What we are demanding right now is accountability. Individual responsibility must be assigned,” said Hossam Bahgat, EIPR’s head.(Reporting by Aidan Lewis; Editing by Sharon Singleton and Marguerita Choy)