The woman who was shot dead by police over the weekend left her home in the wee hours of the night before arriving at City Park at 8am.
Earlier, Ms Janet Waiyaki, 41, had borrowed a vehicle from the mother of Mr Bernard Chege, 26, whom she was in the company of when the shooting occurred. He is recuperating at Avenue Hospital in Nairobi after sustaining gunshot wounds in the incident.
The details came to light as a postmortem conducted on Tuesday showed Ms Waiyaki died as a result of internal bleeding after vital organs were damaged by a bullet.
"There was a bullet on the lower back which went through the organs. Through the liver, the diaphragm and lodged in the right lung. She died of a lot of internal bleeding," Chief Government Pathologist Johansen Oduor said.
The autopsy further showed there were fragments of a bullet on the left shoulder. "Janet was shot twice. There was a bullet wound on the left shoulder. We handed bullet fragments to officers for ballistic examination," Dr Oduor added.
Back to the scene of the crime, Mr Eustace Mureithi, the watchman who called police to report a suspicious car that was parked in the park, refused to disclose further details on the incident, saying he had been advised against it by the police.
"I made the full report at the police station and was told that if you (journalists) need anything, you should use the message I recorded. I've been told not to say anything else," he said.
A night watchman told police that Ms Waiyaki drove the vehicle out of her residence at 2am.
With Mr Chege on the wheel, according to Mr Mureithi, they arrived at the park at 8am. That differs with Mr Chege's account that they arrived at the park between 9.15 and 9.30am. The shooting occurred at 10am.
According to relatives, Ms Waiyaki, a mother of three, was well known to security guards at the park as she was a frequent visitor and confirmed that they recognised her when she arrived.
Mr Chege was the one driving. This tallies with Mr Chege's account that he frequents the spot on weekends and in the evenings.
This raises several questions: why were police called on two people who were well known by the guards, why did police open fire when there was no immediate danger to them or other people?
"That is a public place. The guy who called the police should tell us why he thought the car had stayed there for long. Police should investigate and tell us the truth," Mr Chris Waiyaki, Ms Waiyaki's brother said.
"We are asking ourselves questions. How can the police shoot at a vehicle without a good reason? Are they supposed to shoot if not under threat? They did not aim at the tyres, they aimed at the vehicle. To me, the shooting is still a mystery. There are so many grey areas," he added.
Director of Criminal Investigations George Kinoti said the officers would be required to justify their actions in order to avoid being charged. "The circumstances must be justified. I ordered immediate investigations because officers are always expected to react like human beings when faced by a situation," he said.
Police have said they found the two in a compromising situation in the car, saying both occupants were half-naked at the time of the shooting. The family and Mr Chege, a nephew to Ms Waiyaki's husband, has refuted this on the basis that Mr Chege was fully dressed when they were taken to Avenue hospital.
Two officers who opened fire, together with three others who accompanied them, were disarmed and their guns taken for ballistic examination.
The officers who opened fire are Administration Police Constable William Chirchir from Makadara Lunga Lunga AP post and a regular police constable, Mr Godfrey Kirui from Industrial Area Police Station. They fired 11 bullets.
Other officers present were Constable Christine Manga from Makadara AP headquarters, Mr Kenneth Kirui of Embakasi Police Station and Corporal Bramwel Adala, who was not armed.
Mr Kinoti said officers from different jurisdictions had been sent to Nairobi area command to beef up security around the city centre.
"There is a security alert because of terror threats during Ramadhan. That is why they were deployed in an area outside their usual stations," he said.