Three people are dead and a fourth is fighting for her life after a horrific motorcycle accident near Christchurch.
The motorbikes were travelling in the opposite direction when they collided head on.
Police say one of the bikes was over-taking vehicles when the accident happened.
There was wreckage scattered several metres either side of the highway between Christchurch and Akaroa.
One of the first paramedics to arrive at the scene says it was like a war zone.
"The scene itself on arrival was one of mayhem really. This is a horrendous accident, three motorbikes involved, four involved, three versus 100k an hour open road," says Tony Ward, a Garden City Rescue Helicopter paramedic.
The two bikes that hit each other head-on both carried men whose wives were riding as pillion passengers.
Preliminary investigations suggest a motorbike travelling towards Christchurch was at fault.
"The single motorcycle which was heading towards Christchurch on the Akaroa- Christchurch highway has overtaken a series of cars and this manoeuvre has been done on a sweeping bend which has put him into the path of oncoming group of motor cycles," says Sergeant Chris Jones, the Selwyn District police supervisor.
Police have named the dead as 48-year-old Martyn Hartley and his
35-year-old wife Kaye and 44-year-old Nigel Hannington - all of
Christchurch.
A 47-year-old woman who was a pillion passenger on one of the
motorbikes remains in Christchurch Hospital's intensive care unit
in a serious condition.
She is said to have a torn aorta and serious spinal injuries.
Motorbike riders are always vulnerable on the roads and police are urging extra caution, especially at this time of year.
"If you have a collision on the open road on a motorcycle chances are that serious injuries or fatality," says Jones.
National police road safety spokesman Inspector Rob Morgan says there are now a lot more motorcycles on New Zealand roads.
Police say biking is an inherently risky pursuit and a motorcyclist is 18 times as likely to be killed or injured as someone in a car.
Statistics show older riders are increasingly getting back on their bikes, while others are attracted to them to save money.
Motorcycle skills expert Alan Kirk says there is no denying motorcyclists are over-represented in crash figures. He says motorcycles are much harder to operate than cars.
Kirk says the best survival method is to learn and practice all you can about road riding.
It could be several days before Serious Crash Investigators have their final report into how the triple fatal accident happened.
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