Loading Replay Replay video Play video Play video But residents have been warned to remain vigilant. On Monday, NSW RFS Commissioner Shane Fitzsimmons said emergency services still had plenty of work to do to contain the fire. "We went from more than 500 firefighters yesterday and into last night, and we are now down to just on 250 firefighters, but if we need to, that will scale up again today," he said. "It is still an active fire ground but we are not seeing the sort of weather extremes, particularly with the wind that we saw yesterday.

As the fire front approaches an RFS crew assesses the perimeter at Barden Ridge, Sydney. Credit:Kate Geraghty On Sunday, wind gusts reached as high as 70km/h, making firefighting efforts difficult. While wind gusts were only forecast to reach the 25-35km/h mark, Mr Fitzsimmons said it would still be tough work for firefighters. "It is certainly not the reprieve we look for, it will still be challenging and difficult," he said. "And whilst the threat level has been downgraded to 'advice' ... there is still a lot of fire around." Overnight firefighters backburned along Heathcote Road near Pleasure Point as well as parts of the Holsworthy military base and, on Monday morning, crews were working to slow the spread of the fire with the help of 15 water bombing aircraft.

Captain Craig Byrne (centre) from the Grays Point Rural Fire Service and his crew monitor a fire in bushland in Menai on Sunday. Credit:Kate Geraghty Fire being treated as suspicious Fire investigators alongside NSW Police's Strike Force Carpi were still working to determine the cause of the fire, but Mr Fitzsimmons said it was most likely deliberately lit. "At this stage, obviously we are treating it as suspicious in the absence of any other obvious cause," he said. Liverpool City Police Area Commander, Acting Superintendent Paul Albury said the investigation into the cause of the fire had begun.

"The area where we believe the fire commenced has been forensically examined," he said. "I can say that we have taken a number of statements from people who called the police and fire services in regards to the fire, we have canvassed the CCTV footage and we have also canvassed all the areas around Leacock Regional Park." Acting Superintendent Albury said emergency services were called to several spot fires in the area on Friday night about 9.55pm, and police were looking at whether the fires were linked. "It will be a part of our investigation. It's possible that it's reignited, it's also possible that the fire has been separately lit on Saturday. Mr Fitzsimmons said it was "sickening and reprehensible" to think someone might have set the fire on purpose.

Loading "How dare anyone in society think that they can deliberately light a fire ... and, in turn, put so many members of the community - be they people in homes or businesses or indeed the travelling public - at risk." The latest update from NSW RFS warned residents in Voyager Point, Pleasure Point, Sandy Point, Alfords Point, Barden Ridge, Illawong, Menai and Bangor to remain vigilant, as winds are expected to pick up throughout the day, which could increase the fire activity. The Transport Management Centre said Heathcote Road remained closed between New Illawarra Road and Macarthur Drive, and there was no forecast for when the road would be reopened. The Airport and South train line remains open, and is operating as normal on Monday morning.

Mr Fitzsimmons said residents in the area needed to stay alert. Captain Craig Byrne (right) from the Grays Point Rural Fire Service with his crew watch water bombing as they monitor a fire in bushland off Windle Place in Menai, Sydney. Credit:Kate Geraghty "It is still a very active fire ground which is why we want everybody to remain vigilant, stay across what is going on, listen to radio, watch TV, use the Fires Near Me app and log on to the RFS website for the latest information about what is occurring and what might need to be done if circumstances change. No major loss of property so far Fire and Rescue NSW Commissioner Paul Baxter said it was "remarkable" there had been no major loss of property.

"The most remarkable thing, I think, to me is that we haven't lost a single property yet," he said. "There is still the potential there, but through the hard work of those people, we are looking at a really successful outcome." Mr Fitzsimmons said the fact that only a few fences or garden sheds had burnt down was "extraordinary". Justin Frith hoses down an area behind his home in Menai in Sydney. Credit:AAP Image/Brendan Esposito "I am not being dismissive of the loss in any way, but the fact that this is the loss we are talking about, rather than people's homes being badly damaged or destroyed, is quite significant." 'Unseasonable' weather driving fierce April bushfire