The search is on for a hero who pulled a woman to safety when she fainted on railway tracks in Upper Hutt

The woman was standing at the station platform just before 8am on Tuesday morning when she fainted and fell onto the tracks.

A Metlink spokesperson says the Wairarapa train service was approaching, but not going particularly fast and managed to stop.

A bystander immediately jumped on to the rail corridor and moved the woman off the tracks.

Metlink says they want to thank the people who rescued the woman, but don't know their details so are asking them to call the contact centre.