Police also continue to warn people about seatbelts, drink-driving and speeding, Korach added.
"We keep spouting on and saying stuff like don't speed, wear your seatbelt, don't drink and drive and yet we're still having people speeding, drinking and driving and not wearing seatbelts."
Two people died in separate crashes over two days last week.
One died at the scene of a single-vehicle crash in Mitimiti on Friday morning.
A man in his 40s was also airlifted to Middlemore Hospital with serious injuries.
The Auckland Westpac Rescue Helicopter attended alongside the Northland Rescue Helicopter.
The crash in West Coast Rd, Mitimiti, was reported to police about 7.20am. The road was cleared by early afternoon after being closed for some time.
Kaitāia deputy chief fire officer Ross Beddows said the vehicle appeared to have left the road and gone down an embankment.
Crews responded from several brigades including Kaitāia and Ahipara, but the first on the scene was a fire crew from Whangārei in the rescue helicopter.
The Whangārei firefighters were able to make a start on extricating the seriously injured man, who was trapped, before other crews arrived with heavier equipment.
"He was cut free in a difficult extrication because the vehicle was on its side," Beddows said.
Korach said investigations had so far given no indication of the cause.
"We're waiting for test results to come back," he added.
Another person died after a two-vehicle crash near Kerikeri around 6pm on Thursday, and one was seriously injured.
The incident blocked both lanes of traffic on Springbank Rd/SH10 and the road was closed for some time.
The cause of the crash was still under investigation, Korach said.
Northland Road Safety Trust programme manager Ashley Johnston said people needed to drive to the conditions.
"That is not just limited to weather. People have got to think about the road's condition and how many people are on the road."
Wearing restraints and not driving while impaired were also important, Johnston said, as well as not using the speed limit as a target.
"If the speed limit's 100km/h and the road isn't safe to be driven at 100km/h that's what we also mean when we say drive to the conditions."
The two fatalities bring the Northland road toll for the year so far to 28.
