A human rights group has suggested that as Iran's authorities crack down hard on the escalating anti-government protests, the death toll is rising steeply.

AFP reported that Iran Human Rights (IHR), a Norway-based human rights group, said that as of the 16th day of the protests, at least 648 demonstrators had been killed. IHR said that the dead included nine minors. Earlier, IHR said on the 9th that the death toll was 51, and on the 11th it put the figure at at least 192. The death toll has increased nearly 13-fold in just one week.

IHR said these figures count only deaths it directly confirmed or that were verified by two independent bodies, adding, “By some estimates, more than 6,000 may have been killed.” The number of those arrested is estimated to be around 10,000.

On the 8th, in the Karaj area near the capital Tehran, a 26-year-old man, Erfan Soltani, who had taken part in the protests, was arrested and sentenced to death, and his sentence was reportedly scheduled to be carried out on the 14th (local time).

The U.S.-based Human Rights Activists News Agency (HRANA) said that as of the previous day, protests had continued in 585 localities across all 31 provinces of Iran and that 544 people, including civilians and members of the security forces, had died. The group said it was verifying the authenticity of 579 additional reported deaths.

HRANA noted in particular that videos and information were spreading that numerous bodies were being stored at forensic facilities in Tehran and nearby Kahrizak. Analysis of some of the videos indicated that the number of such bodies could be as high as 250. Iran's state broadcaster IRIB also aired footage showing a large warehouse piled with bodies.

HRANA claimed that 10,681 people had been arrested during the protests and that there had been 96 cases of forced confessions by detainees.

The Iranian government the previous day declared a three-day period of national mourning and defined the casualties as the work of ‘urban terrorists’.