A South Korean appeal court increased the sentence of jailed former president Yoon Suk-yeol on Wednesday to seven years for obstructing justice, up from five years.A lower court had handed Yoon the initial sentence in January after he was found to have used presidential security agents to block his own arrest.Both Yoon and the prosecution lodged appeals. He argued that the arrest warrants against him were based on an “unlawful investigation”, while special prosecutors said his punishment...