"The victim has been identified as Dinesh Bhavchandani (39) who has given a statement against Asaram in the case," said the officer.
"The incident took place when Bhavchandani was riding to his house near Vesu Royal Residency. Two men on a bike overtook him and threw acid," she said.
He was taken to a private hospital.
Asked about police protection for the witnesses, the DCP said, "Most witnesses are given police protection, but these three victims had refused it."
A Surat-based woman has accused Asaram of repeated rapes and illegal confinement between 1997 and 2006 when she was living at his ashram on the outskirts of Ahmedabad. Her younger sister has lodged a similar complaint against Asaram's son, Narayan Sai.
Asaram (72) is currently in a Jodhpur jail after being arrested in September 2013 for sexually assaulting a minor girl at his ashram in Jodhpur.