The Crime Branch, investigating the death of the 28-year -old woman, said they have found several contradictions in the statements given by Nadia's family during the probe.
The investigators are corroborating statements by Nadia's mother Sonia, her two brothers, a maid servant and the NCP leader, who was grilled for nine hours before he went missing.
According to Crime Branch, the ex-minister had met Nadia on May 13 and 14. It is also probing whether the 46-year-old lawmaker was present at her house when she took rat poison.
Crime Branch has also found that Nadia's mother was not in her house when her daughter took the extreme step, a claim denied by Sonia.
The origin of injuries on Nadia's body is also under probe. The postmortem conducted at Chennai after her death on May 30 revealed 14 injuries on her body.
"The postmortem points out that the injuries were afflicted on the body 14-16 days before her death," public prosecutor Sarojini Sardinha said.
Nadia underwent treatment at various hospitals in Goa, Mumbai and Chennai for 15 days before she died.
Sources said Nadia's family members have claimed that these injuries were caused during the treatment.
The statement of a maid servant, who was at Nadia's house when her body was brought from Chennai, has revealed that Sonia had allegedly asked her to burn the evidence related to the case.
Sardinha said the maid has given a statement that Sonia specifically asked her to burn some things in an open place and not in a pit.
The burnt documents included various papers that linked Nadia to the former minister including a boarding pass of Qatar Airways.
The Crime Branch has questioned air officials on the boarding pass, which allegedly shows that Nadia travelled as the spouse of the former tourism minister.
Police are also expecting lead in this matter from the statement of Nadia's estranged husband Wilson Barretto, who in his divorce petition had held Pacheco responsible for the rift with his wife.
Both Pacheco and his close aide and Officer on Special Duty (OSD) Lyndon Monteiro, who have been denied bail are missing. The Crime Branch has now summoned Viola Pacheco, the ex-minister's wife for questioning on Saturday.
Police raided the residence of Pacheco last evening and confiscated several computers as a part of the probe.