肆意横行

Explanation: Wanton: any killing or persecution. Rampant: Zhang Shi evil, violent and rude. Freedom to all kinds of evil. Also as "rampant rampant." 　　Source: Xiu Song "Yu thief On Sapporo child soldiers home": "thousands of miles, the murder and arson, running amok, into the state into counties, such as unhindered." 　　Examples: He lay unarmed 'world', so for the Crown, he is ~ the little emperor. ★ Lao She, "Four Generations" Five