Firefighters desperately try to contain out-of-control fire on NSW Mid North Coast

Fire crews are working to contain a bushfire on the NSW Mid North Coast that has burnt through hundreds of hectares since yesterday.

Emergency services have said the emergency is far from over as they continue to try and contain the bushfire in Bulahdelah, which started yesterday.

Residents in Crawford River are being urged that it is too late to leave and to seek shelter immediately.

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"It started to spot on the paddock I went over, but then a big wall of flames came up the driveway, and I thought I'd better go and protect the shed," a resident said.

NSW Rural Fire Service (RFS) District Manager Ugo Tolone said the fire was "pretty bad at the moment".

"Because it's in thick, heavy tea tree vegetation, which builds up a lot of smoke and runs very hard," he said.

"We are concerned with this fire at the moment, and we are doing everything we can to make the footprint as small as possible."

The fire is in a rural area comprised mostly of farmhouses and sheds, which the RFS says are under threat.

The fire is also causing delays on the M1 Pacific Highway, with just one lane open for almost 100km in both directions and a 60km speed limit.

Temperatures in the high 30s are expected to continue tomorrow.

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