Saudi Arabia which heads one of the panels in UN Human Rights Council said that it has executed 47 "terrorists" on a single day.

Saudi Arabia's interior ministry on Saturday said those 47 included Shia religious leader Nimr al-Nimr and Faris al-Zahrani, a convicted al-Qaeda leader. 

While most of them were Saudi citizens, two foreigners included nationals of Chad and Egypt.

Earlier in December, Amnesty International said the country had executed at least 151 people in 2015, the most beheadings in 20 years.

The executions triggered outrage in a number of countries including Iran, where a mob broke into the Saudi embassy and started fires.

Saudi Ministry of Justice spokesman Mansour al-Qufari told Al-Jazeera, "The judiciary is objective and we deal objectively with the cases on merit. There is no difference between what a person does regardless of his ethnic origin or affiliation, or what he believes. We deal with facts and criminal intent."

However, Nimr's nephew, Ali was not among the 47, who was arrested for similar charges.

Nimr had spent more than a decade studying theology in Iran.

Iran’s foreign ministry called the executions "the depth of imprudence and irresponsibility" on the part of the Saudi government.

Inside the country, people took to the streets in the eastern town of Al-Awamiya. 

UN Secretary-General Ban Ki-moon said he was "deeply dismayed" by the executions.

"Iran executes far more people a year than Saudi Arabia, but it does not get the negative publicity Saudi Arabia has. This is something that must be addressed," Khalid al-Dakhil, a Saudi political commentator told Al Jazeera.