“We have not yet found any particular evidence that can prove Babul’s involvement in the murder,” the home minister told reporters after an award giving ceremony at Tejgaon Adorsho School and College in Dhaka on Saturday.
He further said anyone – whether they are a public servant or a police member or not – would be punished if they committed a crime.
Babul’s wife Mahmuda Khanam Mitu was stabbed and shot to death near her house in Chittagong's GEC intersection area by three men on June 5 last year.
On December 18, Babul admitted that Kamrul Islam Musa, one of the suspects in the murder, was one of his informants.
He made the confession during his interrogation by Additional Deputy Commissioner (North) Mohammed Kamruzzaman of Detective Branch at Chittagong Metropolitan Police headquarters.