Police have released a statement after a video, which allegedly shows a homeless man being attacked in Burnley, was shared hundreds of times on social media.
Officers say they have identified a man involved and they have asked people not to name any individuals linked to the incident on social media.
Their appeal came several hours after the video, which shows a youth hitting a man in a shop doorway, was shared hundreds of times on Facebook and several people put names forward of the culprits involved.
It is believed the video has since been deleted along with the Facebook accounts of those involved.
The police statement said: "We are aware of a video currently circulating on Facebook regarding the alleged assault of a homeless man in Burnley.
"Following inquiries we have identified a male and we will be speaking to him in due course.
"We are at the early stages of our investigation and would encourage people not to name any individuals linked to this incident on social media.
"We will provide an update when we have progressed our investigation."