There is one number you need to remember:
That is the number for the Arkansas State Police Child Abuse Hotline. If you are in Arkansas and need to report a case of child maltreatment, please call it. Please be patient because sadly sometimes it takes awhile to get through, but it's worth it if there is a child in trouble.
After reporting it to the hotline, you need to follow up by contacting your local law enforcment agency (or the agency where the incident is alleged to have occurred). Once again, be patient, but be persistent, because it really is worth it if there's a child in trouble.
If you are outside Arkansas you should check with your local agency to see how to report an incident, but here is a quick overview of how the system works here:
The call to the hotline is very important, because it gets the "ball rolling" so to speak. It is sort of a distribution point for these types of reports. They assess the report and send it off to the appropriate agency to conduct the investigation if there is enough information to trigger an investigation. It also triggers several "time limits" that investigators will be required to follow to make certain the investigation is moving forward. Without that call to the hotline, nothing is triggered, and the appropriate people will not even know about the report and thus will be unable to "do anything about it."
So what is "enough information" to trigger a report? As much as possible, but it kind of depends on the specific circumstances. You should be ready to provide as much as you can, such as names, dates of birth, addresses, phone numbers, etc. to help the investigators get in touch with the parties that are involved, but don't assume you don't have enough information, call anyway, something is better than nothing.
You have to understand that sometimes people "think" a child has been abused, and there really is no basis for it. Just as easily, sometimes people "think" that a child couldn't be abused because the suspect is a really nice person and "would never do anything like that." Call anyway, it's better to err on the side of caution just in case there really IS abuse, and report it. Don't compound the situation by coming unhinged or getting discouraged if there isn't enough for the hotline to accept the report. It happens, you did your part, and don't let one bad experience keep you from reporting in the future. Even if there isn't enough to "trigger" an investigation, it will still generate a record that a call was made, which may help later if more information becomes available.
When calls are screened out without an investigation it is usually because the information was extremely vauge and may have been based on mere suspicion instead of actual evidence or an actual disclosure from the child. Suspicion might not be enough to start an investigation, but it IS enough to pay close attention to the situation and the offender and to report any additional information that may come to light.
A large group of people in Arkansas are "mandated reporters" which means that they have no choice on whether or not to report a case of suspected child maltreatment. School employees, heatlh care workers, counselors, law enforcment, and similar jobs are REQUIRED by law to report EVERY case to the hotline. If you don't fit into the category of a mandated reporter, don't assume that one of them will call the hotline. If you know about the case, call it in anyway.
Do NOT attempt to question the child to get further information. It takes very specific interview techniques to question a child about abuse and still be able to use the information in court. There is also a very real danger of asking leading questions of the child that may lead a child to making a false disclosure. False disclosures have a severe impact on other children that have made real disclosures. It would probably be a safe wager that for every false disclosure, there are many more true ones. But with every false one, people (including judges, prosecutors, jurors, and yes even police officers) tend to have a harder time believing the true ones. That is a big factor in why child abuse cases are very difficult to prosecute.