A Metro passenger was grabbed around the neck and headbutted during an assault on board a train between South Hylton and Gateshead.
British Transport Police (BTP) are now appealing for for information to help identify a man in connection with the assault which took place on Friday, July, 21, between 4pm and 4.30pm.
The incident started at South Hylton station when a man joined a train with a friend, who both appeared to be intoxicated.
A BTP spokesman said: "As the train left South Hylton, one of the men became aggressive and loud, chanting abuse at other passengers and being obnoxious.
"The man then walked around the carriage, and then deliberately fell onto a passenger.
"The passenger, who asked the man to be careful, was then grabbed around the neck by the man and headbutted.
"Thankfully the injuries were not serious.
"The aggressive man then left the train at Brockley Whins station. "
If you know the man in the CCTV images then please get in touch.
You can pass information to BTP by sending a text to 61016 or by calling 0800 40 50 40 quoting reference 1700050203.
Alternatively, contact Crimestoppers anonymously by calling 0800 555 111.