Auckland trains have been halted after a vehicle drove onto the tracks between the Avondale and New Lynn stations.
The vehicle has driven along the rail line after entering via a nearby crossing, only to get stuck on the tracks after the barrier arms came down, a police statement said.
The driver, who appeared to have suffered a medical event, has been taken to hospital in a moderate condition.
The vehicle was not hit by a train, police said.
An Auckland Transport spokesman said the car appeared to be abandoned at the St Jude St crossing.
Fire and Emergency New Zealand (Fenz) northern shift manager Carrin Larken said emergency services were called to the scene shortly after 3pm.
One appliance was sent to the scene.
Auckland Transport warned passengers of delays of up to two hours as workers removed the vehicle from the tracks.
Train services have halted in the area, with trains from Britomart running operating as far as Avondale before turning back.
Meanwhile trains departing from Swanson were running to New Lynn before turning back to Swanson.
Passengers were informed that the 14T and 14W could be used as alternative services that run between New Lynn and Henderson.
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