Police arrested Omar Faruk in Paba, Rajshahi, following an allegation involving a nine-year-old girl.
Local Jamaat-e-Islami representatives identified Faruk as a ward-level rukun.
Both accounts place the arrest on Friday, 31 July, although they differ on whether it occurred in the afternoon or evening.
Paba police said the child’s mother filed a case on Friday night under the নারী ও শিশু নির্যাতন দমন আইন and that Faruk was shown arrested in the case.
In another account, the officer in charge said the mother was preparing to file a case and that police would take legal action after an impartial investigation.
The child’s family alleges that Faruk sexually harassed the girl after she was left alone during a private lesson on 12 July.
The family says the child disclosed the allegation to her mother after returning home.
The mother alleges that the matter was raised with Faruk’s father and that she was advised not to pursue it further.
Faruk denied the allegation, and his father called it false, fabricated and motivated.
A local Jamaat-e-Islami leader called for an impartial investigation and said organisational action should follow if the allegation is proven.
The same leader claimed the incident was two months old, had been resolved between the families, and was later amplified by BNP supporters; those claims have not been independently established.