Iran says in an official report that fewer than 300 people died during protests in 2022 sparked by the death in custody of Mahsa Amini after she allegedly broke the country's Islamic dress code.

The figure is significantly lower than one given by United Nations fact-finders earlier this month.

The Iranian report blamed most of the civilian deaths on "rioters" and said the remainder were involved in "terrorist acts or attacks".

Published on Sunday, the special report from the office of the president estimated that 281 people died in the months of unrest that followed Amini's death in September 2022.

The detailed document, almost 300 pages long, was published nine days after a report commissioned by the United Nations Human Rights Council which accused Iran of crimes against humanity.

Amini, 22, was an Iranian Kurdish woman who died three days after her arrest for allegedly breaching Iran's dress code which requires women to wear a headscarf.

The special committee, charged by President Ebrahim Raisi with investigating the unrest that shook the country after her death, said Amini died of cerebral hypoxia -- a lack of oxygen reaching the brain.

Amini's family had in October 2022 rejected an official medical report that found her death was not caused by beatings.

In its first report since its creation in November 2022, the UN fact-finding mission said "credible figures suggest that as many as 551 protesters were killed by the security forces, among them at least 49 women and 68 children".

It said that "most deaths were caused by firearms, including assault rifles".

According to Iran's own findings, 202 civilians were killed, of whom 112 were bystanders who "were killed during the riots by rioters carrying illegal weapons that were not used by the police".

The remaining 90 civilians killed were involved in "terrorist acts and attacks" against the military, police or public buildings, the report said.

The Iranian commission put the number of law enforcement and security forces killed at 79, and said that hundreds suffered irreversible injuries, such as spinal cord damage and blindness.

Iranian experts concluded in their report that "governmental institutions, including the security services and the judiciary, acted responsibly in the face of the unrest".

In its report, the UN mission said there had been "unnecessary and disproportionate use of force, arbitrary deprivation of liberty, torture, rape, enforced disappearances, and gender persecution" during the protests.

Many of the violations "amount to crimes against humanity", it said.

Tehran strongly condemned the UN findings, saying they were built on "baseless claims" and "false and biased information, without a legal basis".

The Iranian commission indicated that 34,000 people were arrested during "the unrest", of whom 292 were still in custody, with 158 sentenced to prison terms.

Iran executed several men convicted of murder or other violence against security force personnel during the protests.

Experts cited in the Iranian report said that it was "clear" foreigners and outside governments had played a part in the "escalation" of the unrest.

The report blamed Iran's arch-foes the United States and Israel as well as European countries including Britain, Germany and France.