(CNN) -- Effective Saturday night, Yemeni Vice President Abed Rabbo Mansour Hadi took over Ali Abdullah Saleh's responsibilities as president, Yemeni government spokesman Abdu Ganadi told CNN. The power transfer comes as a source close to the Saudi government said that the long-time Yemeni ruler arrived in Riyadh around midnight Saturday, a day after being hurt in an attack on a mosque in his palace. Some Yemeni officials continue to insist that Saleh, who for months has resisted calls to step down, is still in Yemen. Yaser Yamani, Sanaa's deputy mayor, told Yemeni state TV Saturday night that "Saleh is still being treated in the military hospital in Sanaa."
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NEW: President Saleh has arrived in Riyadh for medical treatment, a source says
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Saleh's injuries from Friday's attack on his palace are worse than first thought
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Vice President Abed Rabbo Mansour Hadi has taken over, a Yemeni official says
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All the key players in Sanaa have agreed to an open-ended ceasefire, the source says
The @placeholder government source said Saturday that the Riyadh government has helped to broker an open-ended cease-fire aimed at ending spiralling violence in Yemen.