"We believe, due to the victim's age, that it was an easy target for them, and they entered through the back door," said LAPD Det. Robert Palacios.
Rosenfield returned from the hospital Wednesday morning with a black eye and several other bruises on his face and body.
Police said he was the victim of a home invasion robbery. The suspects stole his wallet, with cash and ID inside.
"Very horrible, he's an old guy, can't defend himself, and two guys come in and beat him up badly. He has fractures in his face. He knows his nose broken. He bled an awful lot," said his brother Martin Rosenfield.
"He told me just yesterday that there had been several break-ins on this block."
Palacios said police believe the suspects are transients, due to the evidence found at the location.
Anyone with information is urged to call the Los Angeles Police Department at (877) LAPD-24-7.
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