The police are currently investigating whether anyone in the mosque and puja mandap committee is behind the incitement of communal violence in Noakhali's Chowmuhani.
In a press conference on Wednesday, Superintendent of Police (SP) Khan Muhammad Rezwan of the Criminal Investigation Department (CID) said that the four suspects accused in the incident, including Iqbal and Ikram, are being interrogated extensively.
"We are investigating if anyone from the mosque and puja mandap committee is involved in the incident," SP Rezwan said.
The officer also informed that the highest technology available to the police is being used to unmask the culprits behind the incident.
Earlier on Thursday, Iqbal was detained by the police from Cox's Bazar.
Later on Friday, he was brought to the Cumilla police lines for quizzing. During the preliminary interrogation, Iqbal admitted to keeping the Holy Quran in the mandap.
The police also arrested three more people on suspicion of involvement in the Cumilla incident. They are Faisal, Humayun and Ikram.
Except for Iqbal, none of the other three have yet admitted to keeping the Holy Quran in the puja mandap.
On October 13, incidents of communal violence spread like wildfire across the country after a copy of the Holy Quran was found on the lap of a Hanuman idol in a makeshift puja mandap on the banks of Nanuar Dighi in Cumilla city.