'Distressing' claims have emerged that police have booked drivers fleeing the NSW fires over unsecured loads, with a Greens MP pledging to get to the bottom of it.

Members of the public alleged in NSW North Coast Facebook groups that evacuees were pulled over when 'these people are fleeing with the only things they have left'.

MP David Shoebridge said he had received reports of people stopped for 'unstable loads' and then being drug tested.

'We will be asking for answers from the Police Minister in Parliament,' he tweeted on Wednesday morning.

Bushfire evacuees have been packed what they can and leaving. Above, a secured load at a property near Koorainghat, near Taree on the NSW north coast on Tuesday

Mr Shoebridge retweeted screengrabs of two posts to Facebook groups devoted to identifying police RBT locations as evidence.

A NSW Police spokeswoman disputed the reports, stressing the 'priority' of officers has been to assist members of the community to safely evacuate their homes.

'While officers may have spoken with members of the community to ensure road users evacuate without incident, the NSWPF has not been targeting road-related offences,' she said.

Mr Shoebridge's office was called for comment and Police Minister David Elliott's spokesman declined to comment.

More than a million hectares of bush have been destroyed and 300 homes destroyed since the beginning of fire season, the NSW Rural Fire Service said.

Fifty homes were lost yesterday as unprecedented 'catastrophic' conditions stretched into the Sydney region.

A Greens MP said he had received 'distressing' reports of police pulling over people with unsecured loads as they fled the fires (stock image)

David Shoebridge (centre) said he will investigate the reports by lobbing questions at Police Minister David Elliott in Parliament on Wednesday

Seventeen fires were blazing from Nowra, south of Sydney, to north of the Queensland border on Wednesday morning.

'Catastrophic' conditions fuelled by scorching temperatures, strong winds and low humidity are expected to calm today.

But NSW Rural Fire Service Commissioner Shane Fitzsimmons told reporters residents are not out of the woods yet.

'Complacency kills. We cannot afford for people to be complacent. We simply cannot rest easy at this stage,'he said.