A pro-democracy media tycoon was sentenced to five years and nine months in prison over two fraud charges linked to lease violations in Hong Kong on Saturday, the latest of a series of cases against prominent activists that critics say are aimed at snuffing out dissidents in the city. Jimmy Lai, who was arrested during a crackdown on the city’s pro-democracy movement following widespread protests in 2019 and under the National Security Law imposed by Beijing, was also fined 2 million Hong Kong dollars ($257,000). His media company, Next Digital, published the now-defunct pro-democracy newspaper Apple Daily. The publication was...