Saudi Arabia said on Sunday two suspects have been arrested in connection with a January shooting attack on two German diplomats in the east of the kingdom.
The two envoys escaped unharmed when their car came under fire on January 13 in Eastern Province, where most of the country's Shia Muslim minority lives.
A spokesman for the interior ministry said a Saudi identified as Ahmed bin Hussein al-Aradi was arrested at the beginning of February and admitted taking part in the attack.
The spokesman, cited by the official SPA news agency, said his interrogation led to the identification of his alleged accomplices, one of whom was arrested.
Protests first erupted in Eastern Province, home to the majority of the country's two million Shias, in March 2011.
Ten people were killed in clashes with security forces, and the fighting intensified after the arrest in July 2012 of Sheikh Nimr al-Nimr, considered to be a driving force behind the protests.
However, tensions eased in August that year when seven Shia dignitaries from Qatif hailed a call by King Abdullah for the creation of a centre for Sunni-Shia interfaith dialogue.
The interior ministry spokesman on Sunday also called for three people named on a list of 23 Saudis wanted in connection with violence in Eastern Province to give themselves up.
He also urged two more, whose names are not on the list, to surrender.