RIYADH (Reuters) - Saudi Arabia has detained 10 more people in a spying case it announced in March that it said was linked to Iran, state television reported on Tuesday.

"Initial investigation carried out by the authorities led to the detention of 10 others for involvement in spying activities," state television news channel al-Ekhbariya reported, citing the Interior Ministry.

It said the new group includes eight Saudis, a Lebanese and a Turk. In March Turki said Saudi security forces had arrested 18 people, including 16 Saudis, an Iranian and a Lebanese. In his statement, Turki said the Lebanese man held in March had now been released.

All of the Saudis arrested in March were members of the kingdom's Shi'ite Muslim minority, leaders of that community said.

(Reporting By Mahmoud Habboush and Angus McDowall; editing by Sami Aboudi)