They said Mohammad al-Nimr was taken into custody by security forces in al-Awamiya in Eastern Saudi Arabia.
Human rights activists have voiced concerns over the latest arrest.
It came a few days after reports emerged that that the Saudi Supreme Court and an appellate court had approved the execution of Ayatollah Nimr.
The reports said the execution warrant has been reportedly sent to Muhammad bin Naif bin Abdulaziz Al Saud, the Saudi crown prince, who is also the first deputy prime minister and the minister of interior of Saudi Arabia.
Ayatollah Nimr was attacked and arrested in the Qatif region, east of Saudi Arabia, in July 2012, and has been charged with undermining the kingdom’s security, making anti-government speeches, and defending political prisoners. He has denied the accusations.
In October 2014, a Saudi court sentenced Sheikh Nimr to death, provoking huge condemnations and criticism in the Middle East and the world.
Ali Mohammed Baqir al-Nimr, the nephew of the prominent Shia cleric and the son of Mohammad al-Nimr, has been also sentenced to death over his alleged role in anti-regime protests in 2012, when he was 17 years old.
http://iqna.ir/fa/News/3399569