Inspector Liakat Ali, former in-charge of Baharchhara investigation centre, used Sub-Inspector Nandadulal Rakshit's gun to shoot Major (retd) Sinha Md Rashed Khan, claimed the investigating team of the Rapid Action Battalion (RAB).
Md Khairul Islam, assistant superintendent of police at RAB-15, told The Business Standard they had already sent the firearm used during the firing for forensic tests to ascertain its owner.
"Thus, we might solve the mystery whether Liakat fired from his own gun or using Nandadulal's one," he added.
He said Liakat and Nandadulal – both accused in the murder case – returned their arms and ammos to Teknaf police armoury as usual after the shooting on Cox's Bazar Marine Drive on the night of July 31.
Following the shooting, Liakat also filed a general diary with Teknaf Police Station.
"Liakat mentioned that he used four rounds of bullet among the issued 30 rounds while Nandadulal submitted all the 30 bullets issued with his gun," said a source based on the general diary.
"It has been confirmed that Liakat shot Sinha with a Torres-Nine MM pistol, but now we have to confirm whether it is his own or not," the source added.
So, a question arises why Liakat did not fire from his own gun.
Another source relevant to the case told The Business Standard that Liakat might not have carried his gun on that night as he was in a hurry to catch Sinha.
"Then, he used Nandadulal's gun. Another thing is that Liakat might have intentionally made a mystery over the killing so that he could frame Nandadulal," the source added.
According to Nandadulal's confession, he was done with his duty at 8pm on that night, and was supposed to go back to his living place in Baharchhara.
"Then Liakat called him several times and asked him to go to the APBn checkpoint to catch a 'dacoit gang' who were coming down from Tuinya Pahar at Marishbunia area. As per Liakat's instruction, Nandadulal went to the spot and strengthened security at the checkpoint. Later, Liakat joined him before Sinha came," the source added.
Meanwhile, the RAB has already made a face-to-face interrogation of the three prime accused, including suspended OC Pradeep Kumar Das and the three arrested APBn members who were on duty on that night.
"We will continue the interrogation for more days to unearth the truth," said an official from the RAB.
Pradeep claims to have been beaten up during interrogation
Pradeep claimed before the court on Monday that he along with his cohort Liakat were beaten up in the RAB custody during interrogation.
However, the investigation officer of RAB-15, Khairul Islam, denied the allegations and told the media that Pradeep was making such claims to evade interrogation during the remand.
Earlier, a Cox's Bazar court placed seven accused policemen in the case filed over the Sinha murder on a four-day fresh remand each.