Police have also confirmed that the incident did not take place on the level crossing at Woodward Road, but was some 150m west of the road, along the track.
St John's Ambulance spokeswoman Ngaire Jones said emergency services were called to a train crossing on Woodward Rd at 3:20pm.
Police northern communications shift commander Matt Rogers said officers were working to identify the dead person.
"At this stage we don't have a full picture about how the person came to be struck by a train."
Mr Rogers said the train driver had given police officers a brief account of the incident.
Train passengers who witnessed the incident would receive victim support, he said.
"They are clearly disturbed by what they've seen."
A Kiwirail spokeswoman said the train driver would receive counselling.
Train services have resumed in both directions on the Western line but there are delays of between 10 and 25 minutes.
- HERALD ONLINE