MANAMA (Reuters) – A Bahraini opposition leader will go on trial this month on charges of promoting violent regime change, the public prosecution and his lawyer said on Monday, in a move that could further inflame tensions in the Western-allied kingdom.

Sheikh Ali Salman, head of the Shi’ite Muslim al-Wefaq Islamic Society, was arrested on Dec. 28 after leading a protest rally against elections that were held in November and which his party boycotted.

“Hearing has been set on 28/1/2015 before the high criminal court,” Bahrain’s public prosecution posted on its Twitter account. “Criminal prosecution for a political association … on charges of promoting the overthrow and change of the political regime by force and threats,” it added with reference to Sheikh Salman’s charges.

Defence lawyer Abdallah al-Shamlawi said in a Twitter message that Salman was facing four charges including promoting regime change by force.

Washington, a close ally of Bahrain which bases its Fifth Fleet there, has expressed deep concern over Salman’s detention and his arrest has sparked protests at home.

The last demonstration was on Friday when around 150 protesters clashed with security forces in Manama. At least two people were wounded by tear gas canisters, and Al-Wefaq sent journalists photographs of men wounded by bird shot.

The island kingdom has been gripped by tension since a 2011 uprising by majority Shi’ite Muslims demanding reforms and a bigger role in running the Sunni-led country.

Authorities quelled that revolt with support from other member states of the Gulf Cooperation Council but sporadic unrest has continued. Demonstrations have increasingly given way to bomb attacks on the security forces. At least two people were killed in two separate attacks last month.

(Reporting by Farishta Saeed; Writing by Amena Bakr; editing by Sami Aboudi and Dominic Evans)

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