Iranian authorities executed last year 582 individuals, human rights groups said, a 75% increase from the year 2021.
The Norway-based Iran Human Rights (IHR) and Paris-based Together Against the Death Penalty (ECPM) said in the Thursday report that four were hanged following taking part in the protests which ignited late last year.
Iran witnessed mass protests starting in September 2022 which were sparked by the death of 22-year-old ethnic Kurd Jina Mahsa Amini, who died while in police custody.
The two groups condemned what they described as an "execution machine."
In 2021, Iran executed 333 people. The groups said they had also counted 151 executions so far this year.
Iran Human Rights Director Mahmood Amiry-Moghaddam said that the execution of the four protesters prompted strong international reactions, making it "difficult for the Islamic republic to proceed with their executions."
"To compensate, and in order to spread fear among people, the authorities have intensified the execution for non-political charges," Moghaddam said.
"Every execution in Iran is political, regardless of the charges," Moghaddam said, describing those sentenced to death on drugs or criminal charges as "low-cost victims" for the regime in Tehran, because their execution was less liable to draw wider condemnation.
As per the report, over half of those executed since the start of the protests were sentenced to death on drug-related charges. In 2022, 49% of the executions were over murder charges.
The groups also highlighted a lack of transparency with announcing the executions. They said that over 88% of all executions and 99% of drug-related ones were not officially announced by the authorities.
Iran met the September 2022 protests with brute force, prompting several Western sanctions and global condemnation.
rmt/msh (AFP, dpa)