The mosque gleams brightly in the sunlight; traffic is as chaotic as always as street vendors hawk handkerchiefs and soft drinks to drivers passing in their cars. There's nothing on Rabaa Al-Adawiya Square in Cairo's Nasr City district to remind people of August 14, 2013.

There's not a trace of blood on the sidewalk, and it is difficult to imagine that the gleaming white mosque was blackened by smoke. The square was closed off for three months. During that period, all reminders of the forcible clearing of the Muslim Brotherhood's protest camp were eliminated.

Alaa Elkamhawy is here again for the first time since those days last August. "It feels just like it did at the time, the anger at the police who were firing indiscriminately," says the photo journalist, who got away with a mere shot in the leg.

He reported daily from the Muslim Brotherhood's protest camp on Rabaa Al-Adawiya Square, where for weeks tens of thousands of supporters of Mohammed Morsi protested the president's ouster. In the morning hours of August 14, 2013, police and the military stormed the square. Between 600 and 2,000 people were reported killed, depending on the source.

Disillusioned, Alaa Elkamhawy peers up at a monument in the middle of the square meant to symbolize the cooperation between the police and the military for the protection of the Egyptian people. It's cynical almost beyond words, Elkamhawy says. "I saw it all with my own eyes - but to this very day, no one has been held responsible for his acts."

Rabaa divides Egyptian society

The crackdown at Rabaa has split Egyptians into victims, critics and backers of the attack, says Ashraf El Sherif. "Egypt before Rabaa is different from Egypt after the massacre; you have a lot of hatred, vengeance and animosities between the different groups," the political scientist says, warning that it doesn't bode well for prospects of national coexistence unless the events are investigated.

Human Rights Watch (HRW) has in fact investigated the crackdown. It interviewed more than 200 witnesses, evaluated video material and screened government documents.

HRW's findings are unequivocal. Events at Rabaa can be termed crimes against humanity, says HRW executive director Kenneth Roth. "They were widespread, systematic attacks on the civilian population, meaning that there was a degree of planning and policy involved."

It was legitimate, many Egyptians say

Roth and his colleagues originally planned to present their report at a press conference in Cairo, but they were barred from entering the country, allegedly because the required business visas could not be issued at the airport in Cairo.

The government, for its part, has decided to strike that day from Egypt's collective memory. A large part of the population shares its view, says El Sherif: "People still think it was a mass killing, but that it was legitimate because it was done by the state against criminals – that's how they see them - and it was also necessary to restore order and to protect the lives of other people."

Elkamhawy adds that the media is largely to blame for this point of view. Over the past months, a massive surge of propaganda launched by the state media succeeded in keeping a firm hold on the privilege of interpreting events at Rabaa. "I'm shocked that the entire society has decided to turn a blind eye on this massacre," the photo reporter says.

'License to kill'

Rabaa is a taboo in Egyptian society. Many protest symbols have been officially banned, including the four-fingered hand sign. In Arabic, Rabaa means "fourth," hence the hand gesture.

The government has refused an independent investigation. Cairo also rejected the HRW report as politically motivated. "This report doesn't concentrate on human rights, it's directed at the Egyptian state," an Interior Ministry official said.

Human Rights Watch is now trying to get international courts to prosecute those implicated, including Egypt's president and former defense minister, Abdel-Fattah al-Sissi, and Interior Minister Mohammed Ibrahim.

"We can imagine that the trauma of such mass killings is great for those who live in a country and can see that security forces can basically do whatever they want," says Sarah Leah Whitson, one of the HRW report's authors. "They can actually kill people in the name of security."

"When there is no accountability, when there is complete impunity - it's a license to kill."