SEOUL, SOUTH KOREA — South Korean authorities detained impeached President Yoon Suk Yeol early Wednesday, the country’s anti-corruption agency announced, following a tense, five-hour standoff at his heavily guarded mountain compound in Seoul. According to local media broadcasts, Yoon’s motorcade arrived at the anti-corruption office, where he is set to undergo questioning in an insurrection investigation related to his short-lived martial law declaration last month. Authorities now have 48 hours to decide whether to file for a formal arrest warrant or release Yoon, whose detention marks the first time a sitting South Korean president has been taken into police custody.