Emergency crews have rushed to Bulli Pass after reports of a truck overturned and well alight.
It is understood the vehicle crashed into multiple power poles before hitting a concrete barrier, flipping onto its side and coming to a halt on the opposite side of the road. It then burst into flames, witnesses said.
Police officers escorted the driver away from the vehicle, down the Pass, according to reports.
Southbound and northbound lanes are closed and motorists should consider exiting the M1 at Lawrence Hargrave Dr.
Police say the road is expected to remain closed all night.
.@NSWAmbulance Illawarra duty operations manager Norm Rees at the “dangerous” scene of a truck crash at bottom of Bulli Pass. Truck mounted a concrete barrier, took out a number of parked cars and hit a power pole. Truck driver taken to hospital with fractured arm @illawarramercpic.twitter.com/DBfhZl9uK3— Andrew Pearson (@andrewrpearson) March 25, 2019
Kerry Davenport saw the accident happen in his rear-view mirror.
"I was coming down Bulli Pass and this truck came behind me out of nowhere - it was flying, it looked like it had no brakes whatsoever," he said.
"I could see it all in my mirror - the truck hit a pole, took out a car and a few more power poles and then crashed through the concrete barrier in the middle of the road and across to the other side and burst into flames.
"It's made a right mess - if that concrete barrier hadn't been there it would have gone through some houses."
Mr Davenport said the truck driver was able to escape the wreckage.
Other residents reported hearing a loud bang before they lost power to their homes.
Lisa Fletcher lives five doors down from where the accident happened.
"There was just a really loud bang and then a second loud bang, and then when I looked out I could see all the power lines quivering," she said.
"I ran outside to see if anyone needed help but most of the neighbours were already out there.
"We saw the young guy get out and made sure there was nobody else in danger.
"Before the emergency services came, the truck caught fire and exploded ... so we naturally got him to safety a bit further back."
Residents were warned by police to stay inside due to concerns over downed power lines.
"Living on the Pass you're used to hearing brakes and then the eventual smash behind it," she said.
"It was just louder than normal and with the bang from the power lines you knew straight away someone had hit something pretty hard.
"The power all went out in the house straight away."
Endeavour Energy reports that 116 homes in Pass Avenue, Bulli, are without power.
Crews are on scene working on returning power, and replacing power poles.
MORE TO COME