The investigators yesterday quizzed Shahadul Islam Sefat and Shipra Debnath as part of the investigation of ex-Major Sinha's murder case.

Sefat was accompanying Maj (retd) Sinha Md Rashed Khan when he was shot dead at Shamlapur police check post on Marine Drive in Teaknaf on July 31 night, triggering an uproar across the country. He is a key witness to the murder case filed by Sinha's sister following the incident.

Sefat, who saw the shooting, was accused in a murder and a narcotics case by Teknaf police while Shipra was arrested under a narcotics case.

Both of them later obtained bail from court.

Private university students Sefat, Shipra, and Tahsin Rifat Noor were in Cox's Bazar to shoot a travel video for Sinha's YouTube channel "Just Go".

Rab also grilled the seven accused in the murder case for the second consecutive day yesterday.

"We are trying to find out who shot Sinha dead and the motive behind the killing," Lt Col Ashik Billah, director of legal and media wing of Rab told The Daily Star yesterday.

Replying to a query, Ashik Billah said three key accused in the case inspector Liakat Ali, suspended officer-in-charge of Teaknaf Police Station Pradeep Kumar Biswas and sub-inspector Nandadulal Rakhshit would be taken for interrogation after the ongoing remand is ended.

The seven people being grilled include suspended policemen ASI Liton Mia and constables Safanur Karim, Kamal Hossain and Abdullah Al Mamum.

The three other accused are Nurul Amin, Nizam Uddin and Md Ayash, who were made witnesses in the cases filed by police. The seven were taken by Rab for interrogation after Rab Senior ASP Md Khairul Islam taken over the charge of the investigation officer (IO) on Friday.

Khairul has a track record of investigating around 600 cases in his 36 years of service career. He is an experienced and skilled police officer, Ashik Billah said.

PROBE COMMITTEE PUBLIC HEARING TODAY

The four-member committee formed by the home ministry to probe Sinha killing is scheduled to hold a public hearing over the killing of the retired army major today. The hearing will be held at 10:00am at the office of Shamlapur Rohingya Camp in-charge in Teknaf.

Shahjahan Ali, Cox's Bazar additional district magistrate and also a member of the probe committee, earlier issued a public statement requesting people to be present at the office and give their witness accounts today.

The public security division of the home ministry formed the high-level committee on August 2 headed by Additional Divisional Commissioner of Chattogram Mohammad Mizanur Rahman to investigate into the incident.

Two other members of the committee are Lt Col SM Sazzad Hossain, representative of the armed forces division of Bangladesh Army and additional deputy inspector general of Chattagram range Zakir Hossain Khan.