The Race star had been due to perform at an open-air venue in Patna when the disruption began, Mumbai Mirror reports.
The actor told the newspaper: "At the venue my troupe and I were waiting backstage when suddenly I heard about a commotion in the audience.
"At first I thought they were just excited but, within minutes, I was told that the situation was beginning to get out of hand."
The concert, which had been organised by a local television channel in Bihar was called off, as organisers began to fear for the safety of the performers.
"They were breaking chairs, pelting stones and setting the barricades on fire. The organisers came backstage and ordered me to leave immediately," Reddy outlined.
The actress was in the UK last month working on the action film Tezz with Anil Kapoor.