The CBI today arrested the sixth person allegedly involved in the murder of National Highways Authority of India’s (NHAI) project officer Satyendra Dubey, from Gaya in Bihar. A CBI spokesman said the person, identified as Pinku, was arrested from Gaya and that he was allegedly involved in Dubey’s murder last year. With his arrest, the number of people nabbed by the CBI in connection with the November 27 murder of Dubey, an IIT engineer, has gone up to six. The CBI arrested Sarwan Paswan on June 13, while it nabbed four others — Babloo Mehtar, Uday Mallah, Mantoo Kumar Paswan and Tutoo Paswan — on June 6. A country-made .315 revolver used in Dubey’s murder and two live cartidges were found under a rock, while the briefcase, containing the identity card of the deceased, some official papers, a bunch of keys and some family photographs, were found in a well near Gaya railway station. After shooting Dubey, the assailants ran away, broke open his briefcase and took out Rs 4,000, the CBI said.According to the agency, Mantu Kumar pulled the trigger, while Sarwan tried to scare Dubey by bursting a cracker, just before he was shot dead.