Activist Shaima al-Sabbagh, who was shot by police, died because she was too thin, Egypt’s medical examiner claims.
Hisham Abdel Hamid, who works for the country's Medical Forensics Authority, said the mother of one did not have enough body fat to survive "the four to five pellets that pieced her skin".
Ms Sabbagh died on 24 January, one day before the four-year anniversary of the Arab Spring revolt in Cairo.
She was among 25 protesters that were attacked by riot police as they gathered near Tahrir Square to remember the 800 people killed there during the Spring protests that toppled the country's then autocratic government.
The mother of one would still be alive had her body not been so slim, Hisham Abdel Hamid said in a television interview on Saturday.
“Her body was like skin over bone, as they say.“She was very thin. She did not have any percentage of fat. So the small pellets penetrated very easily, and four or five out of all the pellets that penetrated her body were able to penetrate her heart and lungs, and these are the ones that caused her death,” he said.
A man who had been standing next to her was shot in the neck and had still survived, he added in defence of the theory.
“These sorts of ridiculous claims just add a thick layer of absurdity to the government’s endless record of killings and impunity,” said Sarah Leah Whitson of Human Rights Watch, who added that at least 17 other protesters died during the same weekend.
Images of Ms Sabbagh being carried away by a fellow activist – reported to be her husband – while dying from body and face wounds propelled President Abdel Fattah el-Sisi to call for an investigation into the incident.
An unnamed officer was charged with battery leading to manslaughter on 17 March.
The Interior Ministry had originally blamed her death on protesters allegedly setting off firecrackers.