The arrested has been identified as Harish Devadiga belonging to Belthangady in Dakshina Kannada district, the police said today.
He was arrested from Pumpwell in the city yesterday and his mobile phone has been seized, they said.
Investigation was progressing and a few more would be arrested in this connection, they added.
The post on the social media also threatened that the member from another community would be taught a lesson if he was again seen with girls belonging to the Hindu community, she had said in the complaint.
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