Emrgency services were called to a block of units in Claymore this morning following reports of a fire in the area.
Fire and Rescue NSW crews from St Andrews and Campbelltown Fire Stations arrived at the scene just after 6am this morning.
The middle of three units was well alight on arrival, and flames had jumped into the roof void, causing the fire to spread to neighbouring units.
Three crews worked to contain the blaze and the fire was controlled less than an hour after their arrival on scene.
The incident was cleared at approximately 8.20am.
There was no one in the units at the time of the fire.
Investigations into the cause of the fire are ongoing.