Rapid Action Battalion (RAB) is preparing to submit the charge sheet in the sensational Tanvir Muhammad Taqi murder case by first week of next month after 11 and a half years of his killing in Narayanganj, an official said.

The investigation in the case has almost completed, Lt Colonel Tanvir Mahmud Pasha, commanding officer (CO) of RAB-11, told BSS Monday.

RAB officials involved in the investigation has so far found involvement of at least 12 people including Ajmeri Osman, son of former Jatiya Party (JP) lawmaker AKM Nasim Osman and a nephew of controversial Awami League leader AKM Shamim Osman, he said.

"We're preparing to submit the charge sheet against at least 12 persons including Ajmeri Osman by first week of the next month," he said, hinting that the number of accused may increase.

RAB has by now arrested Yaar Mahmud alias Parvez, Kajol Hawlader, Abdullah Al Mamun alias Jamai Mamun, Safayet Hossain Shipon, Mamun Miah and Ajmeri's driver Jamshed Sheikh, Pavez, Yusuf Hossain Liton, Sultan Shawkot Bhromor, Rifat, Tayebuddin Jaki, Rajib, Kalam Shikder, Apu and Simanto for their alleged involvement in the murder.

Of the arrestees, Kajol Hawlader, Liton and Bhromor gave confessional statements before the court under section 164 of the Criminal Procedure Code (CrPC) narrating in details how Taqi was brutally murdered at Azmeri's torture centre.

Earlier on 6 March in 2013, Twaki, a highly meritorious A-level student of ABC International School of Narayanganj, was mercilessly killed in Ajmeri Osman's private office “Winner Fashion” in Narayanganj city's College Road area.

His body was recovered from the Shitalakshya River on 8 March, two days after his murder.

Rafiur Rabbi, father of Taqi, told BSS that his son's body was found just a day after authorities published the first year A-level results, in which he got the world highest 297 marks out of 300 in Physics and country highest 294 in Chemistry.

Rabbi alleged that Ajmeri Osman, along with his gang, kidnapped Taqi from Bangabandhu Road of Narayanganj city in the afternoon of 6 March 2013 and took him to Ajmeri’s torture cell at College Road area. They inhumanly tortured Taqi to death and dumped his body in the Shitalakshya River.

Rafiur Rabbi lodged a missing diary with Narayanganj Sadar Police Station on the night of 6 March and filed a murder case without naming anyone on 9 March, a day after his son's body was recovered.

Later, he filed a supplementary first information report (FIR) with a police station accusing Shamim Osman and his son as the masterminds behind the killing.