A policeman was shot dead by masked gunmen in the Qatif district in Saudi Arabia's oil-producing Eastern Province on Wednesday, state news agency SPA said, the latest in a string of attacks there this year.
Four assailants opened fire on a police station before dawn, SPA reported.
Qatif, which is both a city and the name of a district, is home to many Shi'ite Muslims, who form a minority in the conservative Sunni Muslim kingdom.
Qatif was one of three Saudi cities targeted in coordinated bomb attacks on July 4. A suicide bomber struck near a Shi'ite mosque killing himself and two others.
The Saudi government said Islamic State was likely behind the attacks. Islamic State, which follows a hardline Sunni Muslim ideology, considers Shi'ites apostates who should be killed.
There have also been shootings of security forces by Shi'ite militants angry at what they say is repression of their community.
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