It was a battle of nerves.After evading the Federal Investigation Agency's (FIA) summons several times earlier, former president and Pakistan Peoples Party co-chairperson Asif Ali Zardai and his sister, MPA Faryal Talpur, finally appeared before the investigation team in Islamabad on Monday to record their statements in the Rs35 billion money laundering case.During the interrogation that lasted around 25 minutes, a visibly agitated Zardari smoked one cigarette after another as his sister tried to calm him down, narrated one FIA team member who was present during the meeting.At the onset, the former president and his sister, who is currently a member of the Sindh Assembly, arrived at the FIA's offices accompanied by their counsels and other party leaders on Monday morning. The FIA team informed the suspects that they would be questioned without the presence of their counsels. The counsels were subsequently moved to a separate room, leaving Zardari and Talpur alone with the FIA investigators.According to the FIA official, who asked not to be named, Zardari was visibly agitated throughout the interrogation. Talpur, on the other hand, looked more composed and on several occasions, signaled to her brother to stop talking to the investigators. She also inquired about the names and designations of the members of the JIT team, as well as how many belonged to Sindh and how many were from Punjab.The FIA's joint interrogation team tasked to question the duo was led by Additional Director Najaf Qali Mirza. For his part, Zardari kept insisting that the inquiry was initiated by Mirza over a personal grudge. Mirza, on the other hand, reminded the former president that the inquiry had been initiated well before his deputation at the FIA and that the investigation was being conducted strictly on merit.On one occasion, the officials asked Talpur to leave the room so that Zardari could be questioned separately. Talpur refused to oblige, however, and remarked that the FIA had sent joint notices for the investigation which warranted her presence.Throughout the interrogation, the duo kept insisting that the FIA hand over a questionnaire which they would respond to in due time. Talpur told the team that Zardari had stepped down from the post of director of the Zardari Group in 2008. As such, he had no connection with the accounts of the Zardari Group, she said.A member of the JIT then quizzed Zardari about the details of his assets, income and taxes. In response, Zardari said he had paid Rs20.6 million in taxes in the last fiscal year. Before he could say anything further, however, Talpur interrupted and asked him to stop talking. She reiterated her demand for the team to provide a questionnaire so that responses could be filed in writing.At one point during the interrogation, Zardari complained of feeling thirsty. AD Mirza immediately ordered the staff to bring some water. Talpur, however, interrupted again and said that water could be arranged from their own vehicle.Talpur kept demanding that her counsel Farooq H Naik be allowed to enter the room. The 25-minute session ended on the note that the duo would be provided questionnaires to which they can file their responses.However, both PPP leaders were told they could be summoned at any time at a later stage.