Police are hunting two alleged muggers who threatened to stab and then headbutted a man after he asked them for the time in Melbourne's CBD.
The attempted armed robbery took place about 11.30pm on September 4, when the 18-year-old victim approached two men and asked them for the time on the corner of Collins and Swanston Street.
![An image of two men police would like to speak to.](/web/20160930090312im_/http://www.theage.com.au/content/dam/images/g/r/p/8/n/x/image.related.articleLeadwide.620x349.grp8qe.png/1474946114264.jpg)
Police say one of the men responded by allegedly revealing a knife and threatened to stab the victim unless he handed over his possessions.
"The man then headbutted the victim before the two men walked east up Collins Street," Victoria Police spokesperson Belinda Batty said.
Police say the man who allegedly produced the knife and assaulted the victim is perceived to be Sudanese, about 198cm tall and 20 years old.
He was wearing a bomber jacket, red shirt and "snap back" cap.
The second man is perceived to be Caucasian, about 188cm tall and 19 years old.
He was wearing blue jeans, denim jacket and a "stretcher" earing in his right ear.
Investigators have released an image of two men they believe may be able to assist with their enquiries.
Anyone with any information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report to www.crimestoppersvic.com.au