Siya flashed her middle finger as Pune Rural Police took her to her residence in Market Yard, where she and co-accused Chetan Chaudhary allegedly rehearsed the act of pushing Ketan off a cliff at Lohagad Fort, according to investigators.
The police were conducting a probe into the clothes allegedly worn by the accused at the time of the crime.
The garments were recovered during a search of Siya's residence.
Police have also reportedly moved a court seeking permission to conduct polygraph tests on both Siya Goyal and Chetan Chaudhary as the investigation continues.
The alleged murder plot
The case centres on the death of Ketan Agarwal, who initially appeared to have died after falling from Lohagad Fort near Pune during a trek on June 18.
Police later alleged that the incident was a pre-planned murder disguised as an accident.
According to Pune Rural Police, Ketan's fiancée, Siya Goyal (20), and her reported boyfriend, Chetan Chaudhary (22), conspired to kill him.
Investigators claim the duo conducted reconnaissance visits to Lohagad Fort, studied the terrain, remained in constant contact and selected a vulnerable spot from where Ketan was allegedly pushed to his death.
Investigation and arrests
Police allege that Siya initially reported Ketan's death as an accidental fall.
However, inconsistencies in her statement, along with CCTV footage, digital evidence, witness accounts and forensic findings, prompted investigators to register a murder case. Both Siya and Chetan have since been arrested.
Investigators have also claimed that Siya allegedly told them orchestrating Ketan's murder seemed "easier" than confronting her family about her unwillingness to marry him.
Authorities are continuing to investigate the alleged conspiracy, the accused's relationship and possible motives.
The allegations remain part of the police investigation and are yet to be tested in court.