Al-Wefaq said its secretary-general, Sheikh Ali Salman, was among those being questioned
Bahraini police will question key members of the mainly Shi'ite Muslim opposition movement al-Wefaq for what it said were "violations" committed during a pro-democracy rally, Bahrain's state news agency BNA reported on Saturday.
Al-Wefaq said its secretary-general, Sheikh Ali Salman, was among those being questioned and that his house had been heavily surrounded by armed government troops. Bahrain's Ministry of Interior and police were not immediately available to comment.
In 2011, Bahrain stamped out Arab Spring-inspired, mass pro-democracy demonstrations with the help of the Saudi military.
Despite some reconciliation efforts, the tiny Gulf Arab kingdom's Sunni rulers have failed to solve its conflict with the opposition, which says the government discriminates against Bahrain's Shi'ite majority.
BNA reported that a pre-authorised rally of around 2,000 protesters took place late on Friday on Budaiya Highway, which links the capital Manama to the northwestern town of Budaiya.
Organised mainly by al-Wefaq, the protesters gathered under the slogan of "Democracy is our right", the movement said.
"Violations occurred during the rally and members of the organising committee were consequently summoned. The Public Prosecution was notified about the situation," said the northern governorate police general director in a statement to BNA.
He did not elaborate on what kind of violations had occurred.
Al-Wefaq called the move to question is leaders "unacceptable" and accused the government trying to dodge a "crisis with its people".
Bahrain's rulers, along with their Saudi backers, view the Shi'ite demands for political reform as Iranian-inspired subversion.
Their at times violent handling of demonstrations and unrest has embarrassed the United States, which has had to balance its support for an ally that hosts its Fifth Fleet against human rights concerns.