By Sam Holder: ITV News reporter
A 64-year-old Jewish grandfather was attacked so viciously, he didn't even realise what had happened.
The man, who wants to remain anonymous because the attacker still hasn't been caught, told ITV News London in an exclusive interview, that he immediately lost consciousness and broke his ankle after being punched in the face.
His family thought he had suffered a black-out until one of his grandchildren checked the CCTV from the local synagogue and saw the attack.
The victim told ITV News London, "I went into deep shock, terrible pain for the first two nights after I heard it was attack.
"Although I didn't see the footage - I was advised not to - I replayed in my mind what I was told happened, as if I saw it. It was nightmarish."
He has been left in physical pain and suffers from memory loss.
Police believe it was one of four potential antisemitic attacks by the same person on the same day in Stamford Hill - including against a 14-year-old boy.
Despite clear footage of the suspected attacker, he still hasn't been caught almost a week later.
He added: "It's important to me [that he's caught] not because of what happened - that's history - but what he might do next.
"Anxiety levels have risen, which is not very healthy. Especially with this scoundrel at large. People should know these things are not acceptable.
"It's very painful, obviously, I'm in shock. I'm hot, I'm cold, there may be other injuries I'm not aware of. I didn't have my brain checked out but there definitely was some effect on my head. I have memory loss."