A woman has died after being pulled from a unit fire in Sydney’s north.

The top level of the unit block on Allister St in Cremorne was ablaze when emergency services were called just after 7am on Wednesday.

Fire and Rescue NSW crews pulled a woman, believed to be aged in her 60s, from the fire.

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Paramedics treated her for critical injuries but she could not be saved and was declared dead.

She has yet to be formally identified.

The fire was extinguished a short time later.

Police and fire investigators are looking into what caused the fire, and whether it is suspicious or not.