A scrolling message displayed on the digital billboard at Khulna Railway Station triggered tension on Saturday evening.
The message read: "Chhatra League will return again in a terrifying form, Joy Bangla Joy Bangabandhu, Sheikh Hasina will come again."
The incident caused unrest among local students, who gathered at the station to protest.
Leaders and activists from Khulna Metropolitan BNP and the Anti-Discrimination Student Movement arrived at the scene to manage the situation.
Following the uproar, a suspect, identified as Md Aslam Hossain Sentu, was detained by locals and handed over to the police.
Md Ferdous Alam Khan, officer-in-charge of Khulna Railway Police, said: "The incident occurred in the evening when a controversial text appeared on the digital scrolling display at the railway station. The railway authorities quickly shut it down. A suspect who controlled the digital system, identified as Aslam Hossain alias Sentu, was detained by locals and station authorities. He is currently in police custody, and we are investigating the matter to identify the actual perpetrators."
Khulna Metropolitan BNP Member Secretary Shafiqul Alam Tuhin alleged political motives behind the incident.
He said: "The ousted former prime minister and her associates have tried to spread provocative messages, claiming that the banned Chhatra League would return and Sheikh Hasina would come back in a terrifying form. This writing on the main gate of the railway station created unrest. Our activists, along with the Anti-Discrimination Student Movement, surrounded the station and detained the suspect responsible for displaying the text. He has been handed over to the police for further investigation."
The authorities have promised a thorough investigation to uncover the individuals or groups behind this incident.
Meanwhile, calm has been restored at the station as police and railway officials continue their inquiries.