Hurt

I saw a picture of my brother on facebook last week, of him all beat up. It was just his face, but it was all brused and cut up, one eye even swollen completely shut.
He says he doesn't know what happened - he had a concussion and couldn't remember anything, and that all the hospital staff knew was that he was found on the street and taken in my ambulence.
My god.
My little brother (ok, he's my twin, but he's 1 minute younger than me).
I've always been the protective sister, stepping up to dicks who wanted to beat him up or whatnot, so they'll step down (bullies always do if you stand up to them).
But he won't tell me what happened, and I can't believe he just fell down. I'm distraught. I've always protected him (much to his annoyance) and I can't do a single thing because he's 1500 miles away and won't tell me what happened.
It looks like it was one hell of a beating :(