A Knoxville man convicted of drug possession two years ago was exonerated Monday after a judge acknowledged that Des Moines police planted evidence in his case.

Kyle Jacob Weldon pled guilty to possession of methamphetamine in February of 2015 after spending over a month in custody. The Polk County Attorney and the State Public Defender’s Wrongful Conviction Division filed a motion last week to vacate Weldon’s conviction, saying police officers planted the methamphetamine evidence. Last month, two Des Moines police officers resigned after they were accused of planting evidence in at least one drug case. Police officials announced they would be reviewing all cases tied to the officers.