As of mid-April, at least 3,468 Iranians, including 499 women, had been killed since US and Israeli strikes began, according to official Iranian government figures.
This is made up of 1,460 civilians and 2,008 military personnel, state news agency IRNA reported on 26 April.
But the US-based Human Rights Activists News Agency (HRANA) said that their count was higher, with 3,636 killed.
In a report issued on 18 May, HRANA said their figure comprised, external 1,701 civilians, including 307 children, 1,221 military personnel, and 714 individuals whose identity or status could not be confirmed.
The organisation said their documented figures should be seen as “absolute minimums”, as getting information on deaths was severely limited by difficulty accessing sites, government-imposed internet blackouts and political repression.
“Authorities routinely withhold information about casualties, and families may face pressure not to speak publicly about the circumstances of a death,” said Skylar Thompson, the organisation’s deputy director.
Iranian authorities have accused the US and Israel of hitting civilian infrastructure in strikes across the country. Multiple investigations have found that a US missile strike on the opening day of the war hit a school in the town of Minab, which Iranian officials say killed 168 people, including 110 children. The US military has said it is investigating the strike.