Set up a camera outside your home. Stand watch outside your home during the hours you think they will be there. Notify the police of what is happening. Notify any community groups and the local paper.
My neighbors and I have done everything short of setting up the cameras . . . the story in the paper ran under a head like this: LOCAL TERRORISTS MAKING LIFE MISERABLE . . . and it was an above-the-fold front page story (must've been a slow news day).
Anyone got any camera advice?