Investigators found the professors, two Saudis and the rest from neighbouring countries, had been involved with "foreign organisations" based on "voice recordings and emails" linked to them, Okaz daily reported.
It identified the organisation as the Muslim Brotherhood, designated by the interior ministry in March as a "terror" group.
The investigation should be completed by mid-June, said the daily which is close to the government.
If convicted, the group could be jailed for 10-15 years, after which the foreigners would be deported, it added.
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Riyadh had hailed the Egyptian military's ouster of Mohamed Morsi, the Islamist president who hails from the Brotherhood. It has also pledged billions of dollars to the army-installed government in Cairo.
The kingdom, along with other absolute monarchies of the Gulf, fears the Brotherhood brand of grass-roots activism and political Islam could undermine its own authority.
But in the past Saudi Arabia gave refuge to many Brotherhood members who suffered repression in the 1960s under the regime of Egypt's first modern military ruler, Gamal Abdel Nasser.
Saudi Education Minister Khaled al-Faisal was quoted yesterday by media as saying that this was the reason behind the "spread of extremist ideology" in the kingdom.
"We offered them our children and they took them hostage... The society left the stage for them, including schools," he said.