AP Photo / Hasan Jamali
Reuters reported that the rally was one of the largest in the kingdom since 2011, and it marked the third anniversary of the pro-democracy uprising led by Shi'ite Muslims.
Vast crowds of men, women and children took to the streets of the small Gulf Arab nation calling for democracy, political reform and the release of political prisoners, witnesses said.
"We will not stop until we achieve our demands," protesters shouted. "Shi'ites and Sunnis, we all love this country."