"The number arrested to date is 431, most of them citizens, in addition to participants from other nationalities ... six successive suicide operations which targeted mosques in the Eastern province on every Friday timed with assassinations of security men were thwarted," the statement posted on Saturday on the official news agency SPA said.
"Terrorist plots to target a diplomatic mission, security and government facilities in Sharurah province and the assassination of security men were thwarted," it said.
Bloom Gist gathered that the arrest was not carried in one day, but were reportedly made over several days.
Saudi Arabia has taken several steps to stop its citizens joining fighters in Syria or Iraq, with the country's highest religious authority condeming the armed group as "apostates" and labelling them the "number one enemy of Islam".
According to reports, ISIL has recruited thousands of foreign fighters, still controls large parts of Syria and Iraq, where it has been accused of committing mass atrocities against civilians and minority groups.
Saudi nationals have been blamed for several suicide attacks within the country and abroad in recent months.
