SYDNEY, Oct. 4 (Xinhua) -- Water-bombing aircraft were brought in to fight an out of control bushfire in Sydney's outer suburbs on Friday afternoon.

Hot and windy conditions fanned the flames which took hold in bushland near the suburb of Penrith, roughly 50 kilometres from Sydney's central business district.

After initially downgrading the seriousness of the blaze, the authorities issued an emergency warning at around 4 p.m. local time as southerly winds shifted the flames towards houses.

A statement posted on Twitter by the New South Wales Rural Fire Service advised residents to "shelter as the fire arrives," and emergency text messages were sent out to those in the vicinity.

Roughly 100 firefighters were on scene to fight the blaze which reportedly came within 50 metres of properties.

Easing conditions in the afternoon, with some rain predicted, were expected to give fire crews the opportunity to bring the blaze back under control.