Police in South Auckland want to hear from anyone who was at the scene of a crash in which a motorcyclist suffered fatal injuries.
A 47-year-old man suffered critical injuries when his bike collided with a blue vehicle pulling out of Tuakau Rd, in Pukekohe, on Monday, February 22.
He died in hospital four days later.
Counties Manukau road policing manager, Inspector Alison Brand, said police wanted to speak to the occupants of a white vehicle that was immediately behind the motorcyclist when the accident happened about 4pm.
"The motorcycle overtook a white vehicle near the intersection of Tuakau and Bucklands roads, immediately prior to the crash occurring," Ms Brand said.
"We are looking to identify the driver of this vehicle, as it is likely they witnessed the crash."
Officers have also released a photo handed in to them by a member of the public.
In it, a number of people can be seen assisting the motorcyclist just after the crash.
Police are urging those people to come forward also, as they may be able to offer information into the circumstances of the accident.
"The people in this photo might be able to assist with our investigation and we we would like to identify them," Ms Brand said.
"It's important for us to get a clear picture of what occurred at the scene in order to determine exactly what happened and how the crash occurred."
Anyone with information can contact the Counties Manukau Police Serious Crash Unit on (09) 215 6118.