Saudi Arabia's King Abdullah agreed on Wednesday to release Shi'ites arrested after clashes last week in the holy city of Medina after a request from the Shi'ite community, Shi'ite sources said.
The official news agency SPA said King Abdullah met citizens from the Eastern province but did not elaborate. The province is home to the majority of the kingdom's Shi'ite community.
Shi'ite website Rasid.com said the delegation asked King Abdullah to free Shi'ites arrested after a series of clashes in late February with members of the morals police and security near a mosque where the tomb of Prophet Mohammad is enclosed.
Saudi authorities agreed to release 18 Saudi Shi'ites still under arrest and to drop charges against all those accused of disturbing public order, said Toufik al-Saif, a leading intellectual based in the Eastern Province.
Mansour al-Turki, the Interior Ministry's spokesman for security affairs, could not be immediately reached for comment.
Saudi authorities were quoted by Saudi newspaper Okaz as saying Shi'ite pilgrims disturbed public order in the city while one Shi'ite said the morals police prevented them from practising traditional Shi'ite rites.
Morals police often prevent pilgrims venerating tombs, seen as idolatry under the strict Saudi Sunni version of Islam.
Saudi Arabia sees itself as the bastion of mainstream Sunni Islam and is worried about the rising influence of non-Arab Shi'ite power Iran in the region.
(Reporting by Souhail Karam; editing by Thomas Atkins and Philippa Fletcher)