The United Nations has warned civilians are being subjected to a range of human rights abuses with an internet crackdown continuing across the country.

At least 21 people have been executed since the start of the war, with the United States and Israel two months ago - according to UN human rights chief Volker Turk.

More than 4,000 people have been arrested on national security-related charges.

Rights groups have also warned of detainees facing appalling conditions in Iran's prisons - including torture, sexual abuse and being forced to make confessions.

It comes as the family of imprisoned Nobel laureate Narges Mohammadi has raised the alarm over her condition - calling for her to be transferred to adequate medical facilities following a sharp deterioration in her health.