Three people have been killed after a late-night house fire erupted in Sydney’s southwest.

Emergency crews were called to a home on Cornelia St in Wiley Park around 9.45pm on Wednesday after reports of a house on fire.

Fire and Rescue NSW crews extinguished the blaze which had caused extensive damage to the property.

During a search of the home, authorities located three bodies. They’re yet to be formally identified.

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Police have established a crime scene. An investigation into the circumstances of the fire has also been launched.