A case has been filed against three members, including the commanding officer, of Rapid Action Battalion-2 and an informant of the elite force with the Chief Metropolitan Magistrate Court here in connection with the killing of Bangladesh Chhatra League (BCL) leader Arju in a ‘gunfight’ in the city’s Hazaribagh area on August 18.The four accused are commanding officer of Rab-2 Colonel Masud Rana, DAD Shahinur Rahman, inspector Wahid and informant Ratan.Masud Rana, brother of the deceased, filed the case with the court of Dhaka Metropolitan Magistrate Shahriar Mahmud Adnan on Sunday morning.Later, magistrate Shahriar Mahmud Adnan recorded the complainant, said Advocate Azimuddin Shimul, lawyer of the plaintiff.Earlier on August 18, Arju, ex-president of the Hazaribagh thana unit of BCL, was killed in a ‘gunfight’ between his associates and members of Rab-2 in the city’s Hazaribagh area.Arju was the prime accused in the killing of teenage boy Raja, who was tortured to death allegedly by him and his associates in Ganaktuli of Hazaribagh on August 17 over theft of a cell phone set.Sources at the Rab Headquarters said a team of Rab-2 arrested Arju from Hazaribagh area on August 17 midnight.When the Rab team was going to conduct an operation along with Arju to arrest his associates, miscreants tried to snatch the BCL leader from the crime busting force`s custody near Mannan Principal`s house at Boraikhal in Hazaribagh area around 3:30am on August 18, said Director (Legal and media wing) of Rab headquarters Mufti Mahmood Khan.He said as the miscreants fired gunshots, the elite force also retaliated by shooting fire and Arju sustained bullet injuries.At one stage, Arju`s associates fled the scene and the Rab team recovered two foreign-made pistols and three rounds of bullet from there, the media wing director of the Rab headquarters added.Arju was rushed to Dhaka Medical College Hospital where he succumbed to his injuries around 5:30 am.Raja, 16, son of Babul Hossain of 46 Ganaktuli in Hazaribagh, was reportedly picked up by Arju and his associates from his (Raja’s) house and they took him to Arju`s residence in the morning of August 17 alleging that the teenage boy stole his (Arju’s) mobile phone set.The boy was tortured to death later.