Calcutta, Feb. 15 :    Calcutta, Feb. 15:  A chain of relatives of 'prime facilitator' Jamaluddin Nasir played a key role in the American Center attack. With the arrest of two more suspects from Jaipur, investigators in Calcutta are now sure that Nasir's relatives, both close and distant, helped the terrorists at every step, right from renting a room in Hazaribagh to escorting them while on the run. Detective department deputy commissioner of police Soumen Mitra said: 'Four suspects, excluding Nasir and Aftab Ansari, have so far been arrested by the city police and three of them have turned out to be Nasir's relatives.' Earlier, sleuths arrested two of Nasir's relatives -- Adil Hasan and Rohan Alam, alias Monti, from Hazaribagh for helping the gang rent a room there. Monti, a 19-year-old, is the youngest person arrested in this connection. According to sources, though none of them participated in the shootout they helped the killers in their mission. Jaipur police handed over the two suspects, Shaqeel Ahmed and Dilip Patel, to the Calcutta police team which went there early this week. Shaqeel is also one of Nasir's relative. 'The duo is expected to be in the city by tomorrow afternoon,' said Mitra, who is overseeing the attack probe. According to sources, Nasir had gone to Jaipur at the end of last November to buy a jeep (RJ 15-077). 'Ansari told him to collect Rs 2 lakh from Patel, the local hawala operator. We suspect they had a plan to use the jeep in their operations. However, we are not sure so far whether they had any plans to use the jeep in the American Center attack,' an official said. Investigators said Shaqeel lives in Nalanda. He had gone to Jaipur three years ago. 'Shaqeel then started developing his contacts there. He was told by Nasir to keep in touch with the local gangsters,' said an officer. The sleuths suspect Shaqeel had aided in securing safe passage for a consignment of arms to Calcutta. 'A number of facts relating to Shaqeel's role are yet to be verified. We expect some leads after interrogating him,' Mitra said. The five teams formed immediately after the incident to investigate the case are preparing to interrogate Aftab Ansari. 'What I saw in Aftab while interrogating him in Delhi is that he is a cool and calculative person. He is smart enough. He won't confess all the facts. If we want to make him confess, our officers will have to prove that they have enough information on his network,' Mitra said.