Riot police in Bahrain fired tear gas and stun grenades at anti-government protesters whose chants included calls to reject proposed talks aimed at easing nearly two years of unrest in the Gulf nation.

Thursday’s clashes were relatively small, with several hundred protesters demonstrating near Sitra, south of the capital Manama. But they highlight the divides among Bahrain’s Shiite-led opposition over whether to accept the Sunni monarchy’s offers for dialogue.

Appeals to open talks have received a cautious endorsement from main Shiite opposition groups in the strategic nation, which is home to the U.S. Navy’s 5th Fleet. Other anti-government factions, including youth groups, appear to oppose dialogue, claiming the Sunni leadership is unwilling to give up power.

More than 55 people have been killed in the unrest.