Khagrachhari Sadar Police Station OC said that the case was filed against lawyer Imtiaz Mahmud for allegedly making 'provocative comments' on Facebook.
OC Tarek Md Abdul Hannan told bdnews24.com that one Shafiqul Islam filed the case on Friday afternoon.
The plaintiff said in the case that Imtiaz, of late, made various comments on the hill issue on his Facebook page. "His comments generated racial tension in the hill regions. The Bengali-speaking residents are demeaned by calling them 'settlers'," he alleged.
Shafiqul also alleged that the lawyer's Facebook comments were deliberately posted to start a 'riot' in the hill.
The OC said they would investigate the matter and take steps accordingly.