On one occasion he said he saw an Indian man in dark clothing, who appeared to be kneeling and talking to the occupants of the vehicle.
The next time he passed the man had gone.
"I saw an Indian lady sitting at the passenger seat and she looked to me like she was crying," Mr Leota said. "She looked like she was waving and asking for help."
He did not stop and emergency services later arrived
The Crown said Amandeep Kaur and Gurjinder Singh had begun an affair months before Davender Singh's throat was slit as he sat in his car on a Papatoetoe road in August last year.
After 130 calls and more than 1000 text messages in the space of three months, It is alleged their respective partners discovered the relationship and electronic communication between the couple ceased.
But prosecutor Natalie Walker said their contact continued in the form of hand-written notes.
Most importantly, the Crown said the plan to murder Davender Singh was clearly apparent through those letters, which were allegedly found by police after the killing.
Yesterday the court also heard a knife - exhibited in court in a plastic box - was found wrapped in a towel and some bloody clothes under a plastic sheet in Gurjinder Singh's garage.
Forensic testing allegedly found both his DNA and that of the victim on the weapon, it is alleged.