The threat is another sign of the escalating tensions between Saudi Arabia and the United States.
The threat is another sign of the escalating tensions between Saudi Arabia and the United States.
The Haia force must "carry out the duties of encouraging virtue and forbidding vice by advising kindly and gently" under the new rules.
The aim is to increase their employment rate to 24 per cent by 2020.
The leaders are expected to voice support for a bid to unify Syria's opposition at separate talks due to get under way on the same day in Riyadh.
Most of the fatalities came in the holy city of Madinah area, in the kingdom's west, where five bodies were recovered.
United Nations chief Ban Ki-moon was expected to attend the opening in Riyadh of the Fourth Summit of South American-Arab Countries, set to begin at 1600 GMT.