Detectives investigating a brutal double acid attack which left a teenager permanently blinded in Thornton Heath now say it could be a racially motivated.

In the last edition of The Chronicle the 19-year-old who was walking along the road with another man, aged 25, spoke exclusively about the moment when a stranger threw a cup of corrosive liquid over the pair.

He has since revealed his belief that he might still be able to see if the police had acted more swiftly.

The victim, then 18, had been walking to college with a fellow Eritrean refugee at about 8.10am on December 7 when the pair were approached by a man.

The 25-year-old said: “Suddenly, completely unprovoked, the man threw acid at my friend’s face and then my face too. It was more than painful. I was completely blinded. I ran out into the road, not seeing where I was going. My friend ran away, screaming, along Thornton Road.”

The attack was featured on BBC One’s Crimewatch Live and Crimestoppers are offering a £5,000 reward. Detectives believe the attacker previously targeted the teenage refugee on September 7, after he called at the victim’s flat claiming to be delivering a letter.

CCTV footage showed the suspect punching him twice in the face with a bicycle chain wrapped around his fist, before walking off. Police are trying to trace a white van driver who may have seen the assault or even spoken to the attacker before he left the scene.

The refugee who was blinded in the attack said: “I reported the first attack to the police but they didn’t catch him. If they had caught him after the first attack I would not have been blinded in the second one. I asked for help after the first attack but I didn’t get it. With the acid attack the police waited until January of this year to launch a witness appeal. I feel hopeless now.”

The suspect is described as white or Asian, slim, with a black hooded jacket, dark trousers and shoes or boots. He wore a light blue medical mask and a dark baseball cap during both attacks.

Do you know the acid attacker? Crimestoppers-uk.org or freephone 0800 555 111.