Police also continue to seek information from anyone who was in the area of Island Block Rd, Island Block Road bridge and the Whangamarino River on Tuesday between midday and 5pm.
"If you were driving the road during this time and noticed any suspicious activity, please make contact," said Smith.
"Thank you to those members of the public who have come forward with information that has assisted the enquiry.
"We understand these incidents can be distressing, but please be reassured we will hold any offenders to account."
Irfan Qureshi, a spokesman for Airport Masjid and a friend of the fisherman, earlier this week said police had told them they believed his death was suspicious because the chest wounds could not have happened while he was fishing.
Qureshi said the father of four's wife and religious leaders travelled from Māngere to the fishing spot on Tuesday after he failed to turn up to a meeting in Favona.
They were greeted by police.
And a Meremere resident told the Herald this week he returned home just after 5pm to find about five police cars and police divers searching in and around the Whangamarino River.
A rescue boat from the Huntly fire brigade was also helping.
"The whole place was like ... Queen St," the neighbour said.
"They had search lights and everything. The whole place was lit up."
The neighbour said the fisherman was a regular in the area and would often turn up in the morning and fish all day, sometimes staying until sunset.
The man would often give the neighbour a friendly wave from his fishing spot near the Island Block Rd boat ramp where he also parked his car.
"It is a bit suspicious. They are looking for evidence. They haven't left since Tuesday."
The neighbour had been visited by police officers and asked about the likelihood of barbed wire being in the river to which the neighbour told them there wasn't any to his knowledge.
He said it appeared police were now looking for some kind of weapon.
Another Meremere resident was returning from doing her supermarket shopping when she spotted two police cars on the Whangamarino Bridge near the Meremere turn-off on Tuesday at about 10.30pm.
