A key aide to former South Korean president Yoon Suk-yeol has been arrested on charges of attempting to silence negative news broadcasts, as a sweeping investigation into Yoon’s short-lived martial law declaration continues to widen.Meanwhile, special prosecutors, armed with a court warrant, visited Yoon at the Seoul Detention Centre to bring him out of his cell for questioning. Yoon has been refusing to cooperate, citing health concerns.Early on Friday, the Seoul Central District Court issued...