Egyptian security forces have used excessive force against supporters of the deposed President Mohamed Morsi, according to new evidence gathered by Amnesty International.

• Read the evidence:  Unlawful killings on 5 and 8 July (PDF)

Since last Friday at least 88 people have lost their lives in protests and political violence, including three members of the security forces. Around 1,500 have been wounded.

At least 51 Morsi supporters were killed yesterday during clashes outside the Republican guard headquarters.

Hassiba Hadj Sahraoui, Deputy Director of Amnesty’s Middle East and North Africa Programme, said:

“Despite claims by the military that protesters attacked first during clashes on Monday and that no women and Children's rights were injured, first hand accounts collected by Amnesty paint a very different picture. Even if some protesters used violence, the response was disproportionate and led to the loss of life and injury among peaceful protesters.”

The army and Interior Ministry said yesterday that the violence followed an attack by protesters around the Republican Guard Club, and announced that a military officer and two members of the security forces were killed.

However, accounts collected from eyewitnesses contradict this version of events. Amnesty has visited morgues, hospitals and sites of violence in Cairo and Alexandria to gather testimonies from injured protesters and relatives of victims.

Its findings suggest the use of disproportionate force by security forces, including intentional lethal force. Many of those killed and injured had been shot in the head and upper body with shotgun pellets and live ammunition.

Hassiba Hadj Sahraoui said:

“The Egyptian authorities must end the military and police use of grossly disproportionate force. Even when individual protesters use violence, the army must respond proportionately, without killing and injuring those not endangering the lives of the security forces or others. They must ensure an investigation which all sides see as independent and impartial is promptly conducted to ensure any alleged army abuses are not covered up.

“The Egyptian authorities must also ensure that proper autopsy and medical reports are issued to facilitate thorough investigations and ensure access to justice and reparations.

“As politicians squabble over who started the violence, it’s clear that unless the security forces are reined-in and clear orders given on the use of force we’re looking at a recipe for disaster.”

Amnesty’s fears of further bloodshed have been heightened by statements from Muslim Brotherhood leaders vowing to continue protesting until the former President is reinstated, calling on their supporters to “rise up” and “resist”, despite the ongoing deaths and injuries.

A woman in her forties who was wounded on Monday said the violence began at as she finished prayers beside a tent housing women and Children's rights.

“I saw men running towards us, then the teargas started falling,” she told Amnesty. “I did not know what to do or where to take the Children's rights. I couldn’t go back to the tents because we would suffocate, and I didn’t know where to run because of the shooting…There were shots and teargas coming from all directions…There were men lying on the ground in pools of blood in front of me, I just stayed there under the tree praying…I thought that was it.”

Eventually, she managed to escape down a side street.

Amnesty interviewed several other women who had shotgun pellet wounds in the upper body including the back, and a child at a Cairo hospital with wounds in his head, face and legs.

The deaths yesterday followed shootings on 5 July, when security forces shot dead four people during protests in front of the Republican Guard.

Amnesty also found that security forces had intervened too late or not at all during clashes between pro- and anti-Morsi supporters in Cairo and Alexandria on 5 July leading to a loss of life on both sides.

At least eight people died during clashes between rival camps that lasted around five hours in Tahrir Square and the district of al-Manial in Cairo on Friday, with the security forces absent from the scene.

In Alexandria on Friday, at least 17 were killed in the Sidi Gaber area. Security forces arrived on the scene after some people had already been killed. Mohamed Badr al-Din, a local resident, was stabbed and thrown from a roof by Morsi supporters.

A survivor described how he escaped shortly before Mohamed Badr al-Din was thrown from the roof:

“I was chased by a big bearded guy with a huge knife and black flag … He started beating me, and raised a knife saying ‘God is Great’. I escaped from him by jumping down an airshaft, an opening in the middle of the building’s roof,” he told Amnesty.

Local residents said calls for the police to intervene were ignored.

Hassiba Hadj Sahraoui said:

“It is the responsibility of the security forces to maintain security and protect lives. However, instead of preventing further bloodshed they appear to have contributed to it by using excessive force and ignoring the people’s pleas for help.

“Those who violently attack their political opponents should be held to account, whatever their political affiliation.”

• Read the evidence in full (PDF)