Believing they may have the man who pulled the trigger to murder Satyendra Dubey, the CBI today took into custody a 20-year-old after producing him in a Patna court. Sarwan Paswan, a porter, will be in CBI custody for seven days. It’s not clear whether he was picked up from Katari village in Gaya last night or from Patna this morning. NHAI engineer Dubey had complained to the Prime Minister’s Office — it was first reported by The Indian Express — about corruption on a Bihar stretch of the Golden Quadrilateral highway. CBI sources said that Paswan — he did not figure in the original list of suspects — was hunted down after Uday Mallah and Mantu Kumar, two of the four arrested earlier and brought to Delhi for questioning, alleged that he was the man who pulled the trigger. The sources claimed that Paswan has already admitted to the agency that he was present with the others the night they accosted Dubey while he was on his way home on a rickshaw from the Gaya railway station. The CBI has indicated that one or two more persons could be arrested in this connection. The agency hopes to recover the murder weapon with the help of Paswan. The CBI has already videographed the interrogation of the four men brought to Delhi and put through lie-detector tests. These men will now be taken to Patna because their 10-day remand ends on June 15. In Patna, the CBI proposes to confront each with the testimony of the other. CBI sources said that though Uday and Mantu named Paswan as Dubey’s assailant, there were discrepancies in how they fled from the scene of crime. With the arrests, the CBI hopes to file the chargesheet in the murder case within the stipulated 90-day period — they have time until early September — and concentrate on the corruption cases mentioned by Dubey before he was gunned down.