A man in his early 20s with a Salford accent is being sought in connection with the "horrific" rape of a woman at an illegal rave, police have said.
Greater Manchester Police were called to Broad Oak Woods, Carrington shortly after 02:50 BST on Sunday.
A force spokeswoman said a woman aged 18 had reported being raped by a man she believed she had met earlier.
He is described as being white, about 5ft 8ins (1.75m) tall and of a medium build with dark blonde hair.
The man was said to have a Salford accent and was wearing a grey tracksuit, the spokeswoman added.
'No retrospective action'
The force has also appealed for information about three "vicious" stabbings at the event and a video, which the spokeswoman said appears to show three men and a woman "wielding large bladed weapons".
An 18-year-old man remains in hospital in a serious condition, while two others, aged 25 and 26, received treatment but have since been discharged.
An 18-year-old man who was arrested on suspicion of assault remains in police custody.
Det Insp Julian Scarsbrook said people providing information would face "no retrospective action" in connection with attending the rave, as his "interest is entirely focussed on investigating the serious crimes that took place".
"I understand some people may be reluctant to contact police because they were present... and don't want to land themselves in trouble, but I must stress that the severity of these crimes outweigh any self-interests people may possess," he added.
The rave has been widely condemned by local residents and politicians, with Stretford and Urmston MP Kate Green raising the matter with the home secretary in Parliament.
In response, Priti Patel said the rave was "disgusting" and "totally disgraceful".
In a statement, Trafford Council leader Andrew Western said those who had attended had "not only put excessive pressure on frontline services... but also put people's lives at risk".