The Queen's Birthday Weekend road toll has risen to six after a fatal crash in the Bay of Plenty this afternoon.

The holiday road toll climbed twice today after the death of a man in a head-on crash north of Wellington just before 12pm, and the death of another man in a single vehicle crash on Dun Road, Kaingaroa Forest near Rotorua about 3.15pm.

It's the sixth fatal crash on the nation's roads this Queen's Birthday weekend. The first was a four-car crash on State Highway 1, north of Dunedin, on Friday evening.

Police said the man's name would be released publicly once his next of kin were notified.

Another person involved in the crash was critically injured, and a third was seriously injured. Both were flown from the crash site to Dunedin Hospital.

"The serious crash investigator is still conducting enquiries and examinations of the vehicles involved", Detective Sergeant Dave Nelson said.

"A number of witnesses have been spoken to but enquiries are continuing."

On Saturday evening, a person died when three vehicles collided on Omihi Rd in the Greta Valley, north of Christchurch.

Four others were also injured in the collision, which involved a truck and two other vehicles, shortly after 6pm.

Further north, one person died in a two-car head-on crash on State-Highway 3 between Te Kuiti and Piopio on yesterday morning.

Police says two other people were taken to hospital after the crash at 5.32am – one with moderate injuries and one with severe injuries.

In Auckland, a motorcyclist died in south Auckland after colliding with a parked car yesterday.

The crash on Castlebane Drive, in Flat Bush, happened about 4pm and the rider was pronounced dead at the scene.

Additional reporting Stuff.