Passengers in a Wairarapa train that derailed after striking a wandering herd of cattle watched horrified as dozens of animals were left dead and dying in the wake of the collision near Masterton last night.
None of the 57 men, women and children aboard the Masterton to Wellington commuter train were injured in the collision, which happened soon after 5pm about 10km south of Masterton.
At least 22 cows were killed outright and neighbouring farmers destroyed another seven beasts soon afterward, Masterton police Acting Sergeant Celia Donaldson said last night.
But passengers estimated the death toll could be even higher.
Several hundred metres of rail bed leading south from the Wiltons Road level crossing was strewn with the dismembered remains of the dead cows, many of which were in calf, with numerous animals lying dead along both sides of the tracks.
Lyn Murphy, who was seated in the lead carriage with her two grandchildren, said there was an "almighty thud" moments before she saw smoke billowing outside the carriage and "upside-down cows" being flung into the gathering darkness beyond the train windows.
"The children nearly fell off their seats and nobody knew what was happening. Then there was the smoke and a terrible smell - it smelt disgusting."
Nick Smith said he was also in the lead carriage and saw cows being thrown upside-down from the sides of the train "with their legs in the air, and kicking like flies dying".
"I was in a window seat and there was heaps of smoke from the brakes and cows going flying.
"I spoke with the driver and he seemed pretty shaken. He thought there were about 80 cows in the herd and the train killed about 40 of them," he said.
Another lead carriage passenger, Krystyna Porter, said she "felt something hit the train" and saw animals falling into deep ditches running alongside the raised track bed.
"I did see cows going out through a gate just afterward and into a paddock. They looked pretty happy - fresh grass I suppose.
"But there were a lot of cows lying in the ditches and there was smoke and a terrible smell."
Tranz Metro communications manager Lisa Gibbison said three buses were used last night to carry passengers to their destinations and that the lead locomotive of two engines pulling the four carriage train had derailed the first two axles of which were left visibly askew from the rails.
Up to 700 passengers were to be bused from Wairarapa in place of the three morning commuter services out of Masterton today, she said, although the rail timetable would resume as normal once the tracks were cleared and the train rerailed.
Ontrack communications adviser Kevin Ramshaw said last night a crane would be used to rerail the lead locomotive although this may not happen until later today.
He said the Ontrack network ran through about 4000km of New Zealand farmland and trains striking cattle was "rare".
He said there were still four animals tangled beneath the train, which was to be rerailed before noon today depending on the arrival of a crane at the scene.
He said it was too early to consider charges against the owner of the cows, which would be left until the scene could be examined in daylight.
"I can imagine it's a tragedy for the farmer who owns the cattle.
"Our first concern is to clear the tracks and we may look at issues of liability in the light of day."
Herd owner Jan Stolte said last night the cows had wandered on to the track from Wiltons Road and that several hundred metres of fence had collapsed beneath the rush of the surviving animals.
Mr Stolte and neighbouring farmers were clearing dead animals from the track and trackside late last night although he was unaware of how many cattle comprised the herd that was struck.