A chemical spill has caused the evacuation of a warehouse in Palmerston North.

Emergency services are at Turners & Growers warehouse on Mihaere Drive, in Roslyn.

A Fire and Emergency spokeswoman said it was a reasonably significant spill as it had covered about 20sq m.

"The whole building has been evacuated."

FENZ had entered the building to investigate while wearing protective gear because the substance was corrosive, she said.

The first crew had been removed from the scene and were going through the decontamination process, she said.

A police spokesman confirmed that it was called to the scene at about 6.40am.

St John is also on the scene.

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