Saudi security forces have detained 93 people suspected of belonging to the ISIS militant group and foiled a plot to attack the U.S. embassy in the capital Riyadh, the Interior Ministry said on Tuesday.A ministry spokesman said that 15 members of an ISIS-linked cell had been detained for planning to attack security facilities and residential areas and assassinate security personnel.All members of the cell, he said, were Saudi nationals.Another Saudi national, the spokesman added, had been arrested for suspected links with the self-proclaimed Islamic Stane in Iraq and al-Sham (ISIS) militant group.According to the spokesman, the suspect had planned to form a cell with the intention of attacking security forces.The spokesman went on to note that members of a 65-member cell, also said to have links with ISIS, had likewise been detained.According to the spokesman, the cell - which included Palestinian and Yemeni nationals - had been planning attacks in the kingdom and recruiting people for ISIS.The spokesman also said security forces had foiled a plot to attack the U.S. embassy in Riyadh.He said security forces were holding two suspects - a Saudi and Syrian national - in connection with the alleged plot.Saudi Arabia is a member of a U.S.-led coalition that has carried out hundreds of airstrikes against ISIS positions in Iraq and Syria since last summer.The anti-ISIS coalition also includes France, Germany, the United Arab Emirates and Jordan, among others.