Iran rejected human rights watchdog Amnesty International’s death toll at more than 100 in recent protests as “fabricated”, calling the group a “biased” organisation.

Tehran’s UN spokesman Alireza Miryousefi described Amnesty’s figure of 106 dead in the demonstrations as part of a “disinformation campaign waged against Iran from outside the country”.

“Any casualty figures not confirmed by the government are speculative [and] not reliable,” the spokesman tweeted.

In a statement on Tuesday, the UK-based rights group accused Iranian security forces of using “excessive and lethal force” to crush the demonstrations since they started on Friday.

Iran was rocked by nationwide protests sparked by growing anger and frustration after authorities rolled out a petrol-rationing scheme and slashed subsidies in a move that sent prices soaring by 50 percent.

Iranian officials said the steep price increase was imperative because of crippling American sanctions devastating its oil-based economy, and the money raised would be given to the nation’s poorest people.

The government said the price rises were intended to raise about $2.55bn a year for extra subsidies to 18 million families struggling on low incomes.

Amnesty’s report said security forces inflicted brutality on demonstrators in 21 cities, including snipers firing live rounds into crowds from rooftops and helicopters.

“The baseless allegations and fabricated figures by biased Western entities do not shake [the] government’s determination in making prudent economic decisions while respecting human rights of its people, including to freely exercise their right to protest in a peaceful environment,” said Miryousefi.

Authorities said about 1,000 people have been detained over the violence after businesses, banks, and government offices were set ablaze or vandalised.

Thousands joined pro-government demonstrations on Wednesday, state media reported, with television footage showing rallies in Rasht, Gorgan and Ardabil in the north, Hamadan in the west, and Shahryar, south of the capital Tehran.

Iranian dual nationals were among protesters arrested in the northern province of Alborz, according to the semi-official Fars news agency. Quoting security sources, it said detained German, Turkish and Afghan dual nationals had been trained and funded by foreign security services to take actions to destroy infrastructure and stir up civil disobedience.

These dual nationals had special equipment to be used for sabotage, it added without providing evidence or further details.

Rouhani blamed the uprising on “armed anarchists” who took to the streets “based on a plot that the “Zionists and Americans had hatched”