Saudi police shot a man dead on Saturday night in the Shi'ite Muslim district of Qatif, authorities said, in the second shooting incident in two days in the fractious area after months of relative calm.
The deaths bring to at least 20 the number of people shot dead by police since early 2011, when Shi'ites in the Eastern Province staged protests against the involvement of Saudi forces in ending demonstrations in neighbouring Bahrain.
The government said Ibrahim al-Rebah, previously described as a wanted man connected with unrest in the area, was shot dead after exchanging fire with police when he resisted arrest late on Saturday.
Local police said another man, identified by activists as Ali al-Mahrous, was shot late on Friday in an exchange of fire with a suspect, but not found until Saturday morning.
Saudi Arabia last year ordered the arrest of 23 Shi'ite Muslims in the kingdom's Eastern Province, saying they were responsible for unrest that has led to shootings and protests.
Qatif, in the Eastern Province, has Saudi Arabia's largest population of Shi'ite Muslims, a minority that has long complained of entrenched discrimination in a country that hews to the rigid Wahhabi school of Sunni Islam.
Shi'ites say they are passed over for government jobs, that some of their neighbourhoods lack investment afforded to Sunni districts and that powerful clerics employed by the government publicly denigrate their faith.
The authorities deny charges of discrimination.
The deaths are the first in Qatif since early this year, a period of months marked by an uneasy calm in the area after spikes in violence last summer and the previous winter.
Most of the violence has centred on the village of al-Awamiyah on the northern edge of Qatif, an impoverished ramshackle area surrounded by dilapidated fields and bounded on one side by a major gas pipeline.