Rab yesterday arrested the prime suspect in “killing a school girl after rape” in Pakundia upazila of Kishoreganj. The arrestee Pias Mia, 18, is the son of Rubel Mia from Char Faradi village, Rab sources said, adding that they arrested him from West Madarbari area in Chattogram around 2:00am. Earlier on Friday, victim’s mother Angura Khatun lodged a case with Pakundia Police Station accusing some six youths -- four named and two unnamed. The other named accused are Jahid Mia, 20, Ruman Mia, 19, Raju Mia, 19.