Bahraini security forces raided the house of top Shi'ite cleric Ayatollah Sheikh Isa Qassim yesterday, the opposition said, an act likely to enrage the island's majority Shi'ite population, which is at loggerheads with its Sunni rulers.

Bahrain, where the US Fifth Fleet has its base on Iran's doorstep, has been in violent turmoil since Shi'ite-led pro-democracy protests erupted in 2011.

Protests continue and often end in clashes between demonstrators and police. At least two people have died this year.

Security personnel forced open the door of Sheikh Isa's home in Duraz in the early hours of Friday morning and searched the house, Bahrain's main opposition bloc al Wefaq said.

Women and children were in the house at the time of the raid, but the sheikh was not at home, al Wefaq said. No-one was reported hurt.

Bahrain's chief of public security told state media that police in Duraz had come under fire from a "locally made weapon", injuring two officers, and that "necessary measures" were taken "to uncover the source of the gunfire".

Mohammed al Maskati, a leading Bahrain human rights activist, said of the raid: "It's hugely offensive for a huge number of Shi'ites in Bahrain."