Bahrain's government, meanwhile, threatened legal action against the organizers of protests Monday that turned violent. This could herald a new crackdown on Al Wefaq, which until last year was tolerated but which has suffered sporadic prosecutions and detentions after it took the lead in last year's protests.
At least 40 people have been killed during a year of unprecedented unrest in Bahrain. The island kingdom, home of the U.S. Fifth Fleet, was the Gulf Arab nation hardest hit by upheaval during 2011's Arab Spring protests.
The kingdom's ruling dynasty has promised reforms but refuses to make the far-reaching changes that the protesters and Al Wefaq have demanded. These include ending the monarchy's ability to select the government, set key state policies, and appoint most parliament members.
Police fired tear gas at protesters Tuesday in an apparent attempt to preempt a repeat of Monday night marches, in which protesters made their largest effort in months to retake the central Pearl Square. It had been the epicenter of weeks of antigovernment protests last year, and its reoccupation would be a major boost for the movement.
The government statement said many protesters Monday departed from a preauthorized route, turning the march into a riot after police arrived. It said Al Wefaq was responsible for the violence. Al Wefaq said the "unfounded accusations" were part of the rulers' efforts to discredit the group.
Shiites account for about 70 percent of Bahrain's population of 525,000 but say they have faced decades of discrimination. Sunni rulers made token concessions last June ahead of U.S.-supported reconciliation talks between the monarchy and the opposition. But Al Wefaq delegates pulled out of the talks, saying the government was not willing to discuss political reform.
