My Next Door Neighbor is a Rapist

We just found out we have a rapist/child molester living, literally, next door. The guy was convicted of raping a boy in 1992. He was released from prison in 2004. Apparently, he has moved in with his grandfather (or possibly father, we're not sure) right next door. Karma sent an email to all the neighbors to let everyone know. It really has the whole neighborhood on edge. Someone put fliers, with the rapist's picture and arrest info, in neighborhood mailboxes yesterday. When I came home last night, I saw a car parked at the end of the rapist's driveway. The car sat for a minute, backed out and sat on the street for another minute before it finally drove away. I assume it was someone checking out the house. We have not been very diligent about making sure we keep doors and windows locked but that has changed. I have not actually seen him yet but I will definitely keep a watch for him.