MANAMA, Bahrain (AP) — Riot police in Bahrain have fired tear gas and stun grenades to disperse thousands of marchers trying to reach a heavily guarded square that was once the hub of their anti-government uprising.

The clash followed ceremonies Monday to mark the end of Shiite religious commemorations known as Ashoura. It was the heaviest clash in months near Pearl Square, where Shiite-led protesters gathered in February 2011 to demand a greater political voice in the Sunni-ruled Gulf kingdom. It has since been closed off.