The investigation revealed that the Counter Terrorism and Transnational Crime (CTTC) has filed a charge sheet in court accusing three people in the theft of the copper cable of the important telephone connection. The accused are—Ranjan Chandra, an outsourcing worker at the Secretariat, scrap trader Rizakul Islam and Md. Mahabub Hasan. They are currently on bail.

CTTC Additional Deputy Commissioner (ADC) Md. Morshedul Hasan said that from the analysis of information and evidence and interrogation, the incident appeared to be merely a theft. No information was found of any other motive behind it.

The investigation revealed that on May 22, while cleaning the roof of Secretariat Building No. 3, Ranjan Chandra cut the telephone's copper wire with a blade. After the Eid holidays, he sold the wire to the scrap trader.

After public holidays began on May 25, on June 1, the day the Secretariat opened, it came to notice that the Prime Minister's red telephone connection was disconnected. Later BTCL officials restored the connection. In this incident, BTCL official Mohammad Nazid Haider filed a general diary at Shahbagh Police Station. Later, when a case was filed, Ranjan and scrap trader Rizakul were arrested.

Police said that based on information provided by Ranjan, Mahabub Hasan was arrested on charges of buying stolen wire. During the operation, a total of 12 kg 400 g of stolen copper wire was recovered from multiple locations.

According to those involved in the investigation, Ranjan worked as a cleaner at the Secretariat and received a daily wage of 200 taka. Seeing a large amount of copper wire wound on the roof, he became greedy and cut it. Those involved in the investigation said that during interrogation, he also admitted to stealing small items before.