A one-minute video taken on a Metro Light Rail car shows two people beating up someone until another passenger intervenes with a sword.
After pointing the sword at the attackers they get off at the next stop.
The video was uploaded on Oct. 13 and Valley Metro confirmed to KTAR Friday afternoon, the incident is currently under investigation by Valley Metro Rail and Phoenix Police. No other information is available at this time.
In the comments section of the post the author of the video said the incident took place near Central Avenue and Camelback Road around 2 a.m.
*** WARNING: Strong language and racial slurs can be heard in the video.