One protester died of wounds sustained when security forces opened fire on protesters in the Shiite Qatif region of Saudi Arabia's Eastern Province, medical officials said on Tuesday.
Ali Al-Felfel was hit by a bullet in the chest Monday night and died in the hospital later, they said.
Several other people were wounded in the gunfire, which dispersed protests triggered by the suspicious death of a Shiite man near a Saudi police checkpoint in Qatif late Sunday.
Witnesses said Saudi security forces opened fire on protesters that had taken to the streets in the town of Chouika after the death of 19-year-old Nasser Al-Mheishi, accusing police of killing him.
The circumstances surrounding Mheishi's death were not clear.
Speaking to AFP, Mheishi's father said the police told him his son was killed in crossfire between unknown gunmen and police.
But a witness later said that one of the policemen at the checkpoint shot Mheishi dead, according to the father.
Shiite activists told AFP that one other man was wounded in clashes in recent days with security forces in the Shiite town of Awamiya, also in Qatif.
In October, 14 people, including 11 policemen, were wounded during clashes with security forces and demonstrators in the same area.
At the time, the interior ministry in the Sunni-ruled kingdom blamed "outlaws" for the violence and hinted at Iranian involvement in instigating the clashes.
The overwhelming majority of the estimated two million Saudi Shiites live in Eastern Province, which neighbours Bahrain where authorities, supported by Saudi-led Gulf troops, earlier this year crushed a Shiite-led protest.
Shiites in oil-rich Saudi Arabia often complain of being marginalised.