Singareni Colony Faith Baptist Church faithfuls allege that a Hindu right wing group from the locality had planned and carried out the assault. The police who registered cases of rioting and causing minor injury, said an argument led to the clash when the carol team was passing by the wedding procession.
The pastor, Bheemudu Naik, has been admitted to Hyderabad's Yashoda hospital.
"We think it was a spontaneous clash and not a planned one," Saroornagar inspector K Narsing Rao told NDTV.
Nobody has been arrested so far in the case.