A college girl from a minority community was arrested on Wednesday night on charges of hurting religious sentiments in Dinajpur's Parbatipur upazila.
Hours before the arrest, at least five policemen were injured in a clash between police and agitating locals.
Protesters hurled brickbats targeting the law enforcers, and a case was filed yesterday in this regard against 22 named and several hundred unnamed people, said police.
The agitators alleged that the girl made a comment hurting religious sentiments on another's Facebook post on October 27.
A day later, a local social organisation Ridoy-e Parbatipur filed a general diary with Parbatipur Model Police Station in this connection and police brought the girl and her parents to the station for interrogation.
The arrestee claimed she did not make any such comment.
Around 35 people were present there while the interrogation was going on. At one stage, offered everyone an apology while repeatedly claiming that she in no way had anything to do with the comment.
As the issue was settled there, police let the girl and her family members go home, the girl's father told The Daily Star over the phone.
Meanwhile, screenshots of the Facebook post went viral on social media. An "influential person" of Parbatipur played a key role in making it viral, alleged locals.
Around 9:30pm on Wednesday, several hundred locals gathered near Parbatipur Model Police Station and staged a demonstration demanding the girl's arrest.
They burnt tires in front of the station and clashed with police. Hours later, police filed a case against the girl under the Digital Security Act.
In the meantime, the girl and her family sensed trouble and tried to leave the area that same night. They boarded a train from Parbatipur with the aim to go to Shantahar.
But the Bangladesh Government Railway Police (GRP) stopped the train and arrested the girl at around 9:45pm.
She was then handed over to Parbatipur Model Police Station, said Emdadul Haq, officer-in charge of Parbatipur GRP.
Even after her arrest, locals kept staging demonstrations in different areas yesterday, demanding the girl's punishment.
By the time the situation calmed down, it was 1:30 early yesterday.
The incident has spread panic among the Hindu community in the area.
Seeking anonymity, a local level leader of Bangladesh Hindu-Buddhist-Christian Oikya Parishad, told The Daily Star that they are afraid that the protesters might launch attacks on Hindus in the area after Jumma prayer today.
Contacted, Moklesur Rahman, OC of Parbatipur Model Police Station, said police were directed to avoid an untoward situation.
Speaking to The Daily Star, the Parishad's central general secretary said communal and fundamentalist groups found this new technique to torture minorities by spreading rumours on social media.
"I would like to request law enforcers and government high-ups to trace the perpetrators and bring them to book for the sake of maintaining communal harmony."