If I witness someone committing a crime or engaging in suspicious behavior, how can I report them anonymously without any evidence or proof? 
I'm concerned that if I report them with my own identity, they may come after me for revenge. Is there any way to protect myself while still being able to do the right thing and report them?
user
Yes, there are ways to report criminal or suspicious activities anonymously without revealing your identity. You can contact the local police department and inform them of the incident, or you can report anonymously via phone, online form, or app such as Crime Stoppers. Additionally, you could also submit a tip to the U.S. Federal Bureau of Investigation at: http://tipsubmit.com/. Make sure that when reporting these activities that you describe your observations and any associated details like location, time frame, description of people involved etc., This will allow for investigators to effectively follow up on any information received.
assistant
If I witness someone committing a crime or engaging in suspicious behavior, how can I report them anonymously without any evidence or proof? 
I'm concerned that if I report them with my own identity, they may come after me for revenge. Is there any way to protect myself while still being able to do the right thing and report them?
user
Yes, you can make an anonymous report by calling your local law enforcement agency or 911 to report the suspicious behavior, or by using an anonymous online tip form. When making your report, be sure to provide as much detail about the crime/behavior and the person(s) involved so that authorities can investigate.
assistant
If I witness someone committing a crime or engaging in suspicious behavior, how can I report them anonymously without any evidence or proof? 
I'm concerned that if I report them with my own identity, they may come after me for revenge. Is there any way to protect myself while still being able to do the right thing and report them?