Saudi security forces clashed with Shiite protesters in the kingdom's oil-rich east at dawn on Friday, killing one person and wounding three.
Witnesses and activists told Gulf News that security forces opened fire with live rounds after protesters hurled stones at one of their vehicles in the Shiite village of Al Awamiya in the Qatif region.
Activists identified their slain comrade Essam Mohammad, 22. He was killed by multiple bullet wounds, they say.
According to the report, three other people were wounded when security forces opened fire, one of them a man driving through a checkpoint at the entrance to the village.
Security forces sealed off the village after the clashes, witnesses said.
Protests erupted in Qatif Province in March when members of the kingdom's Shiite minority flooded the streets in protest of Saudi Arabia's military intervention on behalf of Bahrain's embattled monarch.
Sunni-ruled Bahrain sought Saudi aid against Shiite-led pro-democracy demonstrations that set off tremors in the tiny island kingdom.
Four Shiites were also shot dead in Qatif in November 2011. The interior ministry said security forces had come under fire from gunmen operating on "foreign orders," in a veiled accusation against Shiite Iran.
Most of Saudi Arabia's estimated two million Shiites live in Qatif Province.