Police arrested a suspect in connection with Kashimpur jail guard Rustam Ali murder at Joydevpur of Gazipur on Monday night.

Sub-inspector Enamul Haq of Joydevpur Police Station said a local police team caught Himel, 22, son of Hasan Ali of Deoliabari area in Gazipur city, during an overnight drive.

Himel is one of the four named and prime accused in the murder case filed by Rustam's wife Nasrin Akter with Joydevpur police yesterday, said the SI.

Nasrin also mentioned five unnamed people in the case statement for killing her husband, added the police official.

In broad daylight on Monday, bike-riding criminals gunned down Rustam, 60, yards away from the gate of the high-security prison in Kashimpur. 

Police said following the incident, they had picked up several people, including Nasrin, for interrogation.

Of those picked up by police include Sohel Rana, husband of Rustam's adopted daughter Nahida, and Saiful Islam, owner of the pharmacy in front of which the prison guard was shot dead, said police sources.

Rustam, who was promoted to sergeant instructor before he went on leave preparatory to retirement (LPR) in November last year, was sitting in front of the pharmacy about 150 yards from the prison gate.

Two to three assailants on a motorbike shot him from close range around 11:15am on Monday, leaving him dead on the spot, said locals and the prison authority.

The criminals then fled on the motorbike.

The prison authority suspected that there might be a militant link in the killing.

Gazipur police said they would investigate whether any possible militant or any family dispute was behind the murder.

Except police investigation, the prison authority formed a three-member committee, led by Deputy Inspector General (prisons) Golam Haider of Dhaka, to look into the incident.