A "massive" bushfire has burnt nearly 2,500 hectares in Sydney's southwest .
Barden Ridge. Photo: Twitter / MikeCirca1981
The blaze began on Saturday and needed more than 500 firefighters, almost 100 fire trucks and 15 aircrafts to bring it under control.
The NSW Rural Fire Service says it can't yet confirm the level of damage and the number of properties affected, but the fire had burned 2,430 hectares around the Holsworthy and Menai areas and damaged an army base.
Firefighters and residents worked through the weekend to fight fires and battle ember attacks. After initially easing, the fire flared up again on Sunday.
Lighter winds saw the alert level for residents downgraded from an emergency warning to a "watch and act". Residents in nearby suburbs have been warned to watch for spot fires.
NSW Police have launched an investigation into the cause of the fire and are appealing for witnesses
