Kamal told private station Independent TV on Sunday night: “The file from the Police Headquarters includes Babul Aktar’s resignation letter written by him.”

“The matter is awaiting our decision. We will make the decision soon,” he added.

Motorcycle-borne assailants killed Babul’s wife Mahmuda Aktar Mitu in the port city on June 5, a few days after the SP was transferred to Dhaka from Chittagong.

Police had first suspected the hand of militants in the murder, as Babul had led several successful anti-militancy drives in Chittagong and the way his wife was killed was similar to the recent spate of killings claimed by Islamist militants.

Later after several arrests, the security forces said it was an attack by ‘miscreants’.

On June 24, sleuths whisked away Babul from his in-law’s house in Dhaka and apparently quizzed him for 14 hours.

Babul went to the Police Headquarters on Aug 3, but did not join work, officials said.

He has been with his children at his in-laws’ house in Dhaka since the murder.

Inspector General of Police AKM Shahidul Hoque said he had heard Babul “is mentally depressed and is not in a state of mind to continue work”.