Based on a digital analysis of scores of rapid-response messages following the killing on Saturday, a hub of communist and socialist nonprofit organizations emerged as key organizers of the protests. Many of them are funded by American-born billionaire Neville Roy Singham, a self-declared Marxist-Leninist living in Shanghai. Some are also offshoots of the People’s Forum Inc., a nonprofit hub Singham has funded in New York City since 2017 as an “incubator” for socialist and communist groups. The People’s Forum declined requests for comment.