Do released offenders influence the criminal behavior of individuals in the neighborhoods they rejoin? Using a unique dataset on arrests, prison releases, and places of residence for the universe of men in Ecuador and exploiting a mass pardon in a difference-indifference design, I find evidence that released offenders contribute to increased criminal activity among their neighbors. On average, one additional release leads to an increase of 0.85 arrests, excluding the released offenders themselves. First-time offenders account for 42% of this effect, with the primary mechanism being the spread of criminal behavior through peer and family networks. These peer effects are larger for defendants who served longer portions of their sentences, suggesting that time spent in prison may intensify criminal behavior. Finally, I show that access to job training programs during incarceration can help mitigate these effects.