"One vehicle came out of a driveway and T-boned another car travelling on SH16. The damage was quite bad."
St John ambulance spokesman Robbie Walker said two people, their ages and sexes unknown, were taken to Auckland Hospital in serious conditions.
Mr Wakelin said the second crash in Pt Chevalier occurred at 7.20am near the motorway on-ramp when a bus hit a car with a woman and children inside.
"There was a female in the car and some kids, they were quite shaken," he said.
Mr Walker said three people were treated at the scene but did not require hospitalisation.
An Auckland District Health Board spokeswoman said the victims were a male and a female and were in serious conditions.
Mr Wakelin said the crash caused heavy traffic congestion.
"Initially we had two lanes blocked. They were cleared by 8.05am but there was quite a bit of build up after that."
At 8am, a male motorcyclist in his 50s was killed in a crash with a ute in the settlement of Longburn near Palmerston North.
A statement from police said the crash happened on SH56 at the intersection of Walkers Rd.
"Attempts were made to resuscitate the motorcyclist ... however he was pronounced dead at the scene," the statement said.
"Officers are speaking with witnesses including the driver of the ute who did not sustain any injuries but is shaken from the crash."
The road was also closed, but diversions were now cleared.
