Police are appealing for witnesses after two men were partially blinded when they had chemicals thrown in their faces in Salford.
The first incident happened at about 8.30pm on Saturday 17 October 2015 when a 20-year-old man was riding his scooter along Eccles New Road.
Two men stood in the middle of the road and tried to block his path, so he turned into Foster Street but the men followed him.
He tried to escape back onto Eccles New Road but the men followed again and as he rode past them, one threw liquid into his face and both fled.
The man immediately suffered a total loss of vision and went to hospital for treatment. The men are described as both wearing dark clothes.
The second incident happened between 6pm and 6.30pm on Friday 30 October 2015 on the A5063 as it approaches Liverpool Street.
A 24-year-old man was driving along the road with his window down and as he stopped at the traffic lights, a car pulled up and a man from the car squirted liquid in his face.
The man had a total loss of vision in one eye and suffered burns to his face. He also went to hospital.
The men in this incident are described as being white and between 17 and 19-years-old.
The liquid used in both incidents is believed to be ammonia or hydrogen peroxide.
Both men are recovering but have not regained full vision.
Detective Constable Sue West of Salford division said: “These attacks were totally unprovoked, and it has left both victims with potentially life changing injuries.
“We believe that these incidents may be linked and I am appealing for witnesses to help catch the men who did this.”
Anyone with information is asked to call police on 0161 856 5361 or the independent charity Crimestoppers, anonymously, on 0800 555 111.