A man has been detained for five days by Beijing police after he poured water over the head of Baidu CEO Robin Li as he delivered a speech at a conference, authorities said Thursday. Li was speaking about Baidu’s autonomous car development at an event on Artificial Intelligence on Wednesday when the man stormed onto the stage and emptied a water bottle over his head. The tech billionaire, who co-founded the internet giant, stood stunned for a moment as the water poured down his face.