Bahraini police have used tear gas to disperse the demonstrators, protesting in the capital Manama against the arrest of the country’s opposition leader, a RIA Novosti correspondent reported Sunday.

Shiite opposition supporters gathered during an unauthorized rally to demand the release of Sheikh Ali Salman, the leader of the largest Shiite opposition party Al-Wefaq, who has been under investigation since last Sunday. The demonstrators were holding photos of Salman and screaming out slogans in support of Salman’s release.

Security forces used tear gas to disperse the unauthorized rally and arranged the police stations along the road, which connects the Shiite villages in the west of Manama to prevent the demonstrators from going there.

Sheikh Ali Salman was arrested on December 28, in Bahrain. On Monday, December 29, charges of “inciting violent change of regime through threats and illegal practices,” as well as “public insult of the Interior Ministry” were brought against Salman. The move aroused concern of the United Nations, the European Union and the United States.