The girl and the man in the video have not yet been identified, Alabama investigators said.
The Lubbock Police Department has received one police report regarding the video and suggest people also not share the video, even if the intentions of sharing are good.
Police say once the image is reported on Facebook, the company will notify law enforcement immediately.
"When you receive you are actually a victim yourself, but when you share it you become a predator, a suspect and charged may be drawn up on you", Sgt. Loloita Rosser said.
A message containing a video depicting child pornography has been spreading through Facebook's Messenger feed.
"It's going viral and we don't want it to go viral, " Tony Garrett, executive director of Central Alabama Crime Stoppers, told AL.com "It's already disturbing enough".
The Kent County Sheriff's Office said it is investigating the matter.
Never click on or open unsolicited emails or messages from unknown contacts.
Immediately delete the file and all record of the communication.
After the video began circulating Facebook, several law enforcement agencies throughout the country began investigating.
Check privacy settings and account security.
They say some recipients may think sharing the video could help find the person responsible for it. Please visit the FBI's Safe Online Surfing website for additional information.