The teenager was wearing his camouflaged uniform having spent the day in the city centre selling poppies and collecting money to commemorate Remembrance Day.
As he was looking down Princess Street for his bus, he was approached by a black man who, without warning or provocation, produced an aerosol can and a lighter which he used to spray lit fumes in the direction of the unsuspecting teenager.
His attacker has been described as 5"8', black or Asian, and wearing a dark hooded top. He also appeared to be under the influence of alcohol, police said.
Detective inspector Liam Boden of Greater Manchester police said:
This is an absolutely appalling attack on a young man who was raising money to help remember all those who gave their lives fighting bravely for their country.
At this stage of our inquiries, we're keeping an open minded as to what motivated the offender to commit such an act.
Given the initial description we have of the offender, it may be that he was under the influence of something but whatever his motivation, his violent actions could have scarred this young man for life. Although he has suffered some minor injuries, it is pure luck that he did not sustain more serious burns to his face and body.
Understandably both he and his family are in a state of total shock and cannot believe someone would do this.
Police are now appealing for anyone with information to contact them on 101 or speak anonymously to Crimestoppers on 0800 555 111.
