It was unclear how far the derailed train had come off the track.
The train drivers were both shaken but otherwise unhurt, he said. There were no immediate reports of injuries among the passengers or crew, but KiwiRail was waiting for more information.
The northbound train was carrying 40 passengers and three train staff, and the other train had 14 passengers and three staff on board.
Central ambulance communications team leader Penny Poutu said staff were still assessing passengers.
"But the last information I had through was that patients from each train were walking and talking," she said.
Police Sergeant Mike George said five people had minor injuries.
The last of the passengers were evacuated from the trains at approximately 4.45pm and taken to Monteiths Bar in Mana.
One of the passengers described the collision as "a bit rough".
When asked if it was scary, he said yes.
Major travel delays
Commuters travelling by train north of Wellington this evening should expect delays.
All trains heading north from Wellington on the Paraparaumu line will leave at half hour intervals and will stop at Porirua, where buses will pick up passengers.
The Capital Connection service, which goes between Wellington and Palmerston North with stops in Waikanae, Otaki, Levin and Shannon, will be replaced by buses from Wellington.
Meanwhile, a slip has also blocked off another major line in the Wellington rail network. TranzMetro says services are not operating on the Johnsonville line due to a slip and bus replacements are unavailable.
- NZ Herald staff and NZPA
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