The three were given first aid at a medical centre and discharged, they said.
The escalator, installed at platform No 1, all of a sudden started moving in the "reverse direction", leading some of the passengers riding on it to lose balance and fall, they said.
Three of them, identified as Kuldeep Ware, Tejashri Mishra and Sunil Thakur - received injuries, the police said.
The escalator has been shut for repairs.
Station officials could not be reached for comments on the incident.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)