Human Rights Watch called on the Egyptian government Monday to stop using live ammunition against protesters, as it challenged the official death toll from day one of the ongoing crisis.
In a statement, the New York-based human rights group said the large-scale use of live ammunition was not only unjustified, but also a failure to abide by international policing standards.
With the death toll mounting every day, Egypt's military rulers should "urgently reverse" police instructions to use live ammunition to protect state buildings, it said.
Such lethal force should be used "only when strictly necessary to protect life," it added.
"This excessive and unjustified use of lethal force is the worst possible response to the very tense situation in Egypt today," said Human Rights Watch's acting Middle East director Joe Stork.
"Egypt's military rulers should rein in police forces to prevent the country from spiraling into further violence. The military should not be encouraging police to use even more lethal force."
Investigating the August 14 crackdown on the Rabaa al-Adawiya protest camp that triggered the ongoing crisis, Human Rights Watch said the death toll "appears to be at least 377" -- higher than the figure of 288 released by Egypt's health ministry.
Human Rights Watch cited "first-hand documentation" and interviews with health workers, as well as a list of fatalities from the Egyptian Center for Economic and Social Rights, as the source for its toll.