Officers have released CCTV images of people they would like to speak to following an assault at a tram stop.
At around 11pm on Saturday 25 July 2020, officers were called to a report of an assault on four people on the Metrolink at St Werburghs.
Four people were injured, including two who were hit over the head with a bottle.
Inspector Amy Tierney, from GMP's Transport Unit, said: "This was an unprovoked attack on four people travelling on a tram. They all received injuries as a result of this assault which required medical treatment.
"We are keen to bring those responsible to justice and are now appealing for anyone who recognises those pictures to come forward.
"Anyone with any information or recognises anyone in the images is asked to call 0161 856 1855 quoting log 3879 of 25/07/20.
"Alternatively, information can be passed anonymously to Crimestopppers on 0800 555 111."