Fifteen people have been sentenced to death by a Saudi court for spying on Iran, Saudi privately-owned al-Arabiya news broadcaster reports.
The charges against the group include plotting with Iranian intelligence against Saudi Arabia, and some of the convicted spies had allegedly met with Iran's Supreme Leader Ali Khamenei.
They have also been found guilty of offering Iran confidential military intelligence.
A total of 32 suspects were referred to trial earlier in February. They include 30 Saudis, one Afghan and one Iranian.
The broadcast report did not give details on the nationalities of those sentenced on Tuesday. The verdict can be appealed.
The fate of the other 17 is still unknown.
The case comes as a regional rivalry deepens between Saudi Arabia, a Sunni monarchy, and Iran, led by Shiite clerics.
The two countries currently back opposing sides in the Syrian and Yemeni conflicts.
Saudi Arabia has long faced unrest among its Shi'ite minority, which charges that the government discriminates against them in all aspects of life, including economically and religiously.
A total of 30 of the defendants were from the al-Qatif region, in the east, which is predominately Shi'ite.
