The police officer said Pawan Insan was arrested late in the evening. He was booked for allegedly inciting violence in the wake of the Dera chief's conviction in a rape case by a CBI court in Panchkula in August.
He is the former spokesperson of the Dera chief and used to manage media outreach for the self-proclaimed godman.
Another close aide of the sect chief, Aditya Insan, who is also wanted for allegedly inciting violence, is still on the run, the police officer said.
Pawan Insan, Aditya Insan and Honeypreet have topped the list of 43 "wanted" people. The list was released by the state police in September in connection with the violence following Ram Rahim's conviction.
At least 41 people died and several others were injured in the violence. The Dera chief was sentenced to 20 years in prison for raping two women.
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