A Saudi court on Wednesday sentenced 22 Saudi citizens, an American and a Yemeni to jail terms of between two and 27 years on terrorism charges, Reuters reported, citing the official news agency SPA.
The court said charges ranged from "the establishment of a terrorist cell planning to targeting oil pipelines," having weapons, and planning attacks and at home and in neighboring Bahrain.
The U.S. citizen, who was not identified, was sentenced to 17 years backdated to the start of his detention six years ago for "cyber crimes", the court said, without elaborating.
He will be deported on completion of his sentence, according to Reuters.
Saudi Arabia has been cracking down on terrorists, both on those within the kingdom as well as on those who leave the country to fight abroad.
In February, the Saudi king decreed jail terms of up to 20 years for belonging to "terrorist groups" and fighting abroad, in another attempt to deter Islamist Saudis from becoming jihadists.
In early March, Saudi Arabia blacklisted the Muslim Brotherhood and two Syrian jihadist groups as terrorist organizations, ordering citizens fighting abroad to return home within 15 days or face imprisonment.
The kingdom has also banned the sale of books by two Islamist authors known to be sympathetic to the Muslim Brotherhood.
In June, Saudi Arabia sentenced 33 suspected Islamist terrorists to up to 30 years in prison.