RIYADH: Saudi police have arrested a Shiite cleric in Eastern Province, home to the kingdom's minority Shiites and scene of sporadic anti-government protests, activists said on Tuesday.

The activists, who spoke to AFP on condition of anonymity, said police had arrested Sheikh Hussein Radi at his home in the eastern town of Amran on Monday night.

They said he was likely to have been detained for taking part in protests last week against the anti-Islam film "Innocence of Muslims" that sparked a wave of violent demonstrations throughout the Arab and Muslim world.

Interior ministry spokesman Mansur al-Turki told AFP he was "not aware" of the arrest, but added the cleric may have been brought in "just for questioning."

Sheikh Radi is one of about 70 Saudi Shiite clerics who released a statement addressed to "decision-makers in the Muslim world" demanding they take a clear stance on the anti-Islam film.

Hundreds of Saudis took to the streets last week in protest over the film, despite a long-standing ban on demonstrations in the kingdom.

Since early 2011, the mainly Shiite towns and cities in the east have seen sporadic protests and confrontations between police and marginalised Shiites who are estimated to number about two million.

Unrest erupted after an outbreak of violence between Shiite pilgrims and religious police in the Muslim holy city of Medina in February 2011.

The protests escalated when the kingdom led a force of Gulf troops into neighbouring Bahrain the following month to help crush a Shiite-led uprising against the Sunni monarchy there.

Ten people have been killed in the violence.

Rights groups say more than 600 people, mainly Shiites from the eastern region of Qatif, have been arrested since spring 2011, but most of them have been released.