Up to 380 vehicles have had their tyres punctured after tonnes of steel shards were scattered along a major NSW highway.
More than 25km of the M1 Motorway north of Sydney was closed on Friday after a truck carrying metal debris spilled its contents at about 5am.
The shards were scattered along the southbound lanes, slashing the tyres of hundreds of vehicles driven by unsuspecting motorists.
Like trying to 'hoover up the highway'
It was a difficult task to comb through small pieces of metal that could be easily lodged in crevices and tyre treads, NSW Roads Minister Jenny Aitchison said.
"This is an unprecedented situation," she told reporters on Friday.
"It's like trying to hoover up the highway.
"We're very lucky we haven't had a fatality."
A 20km stretch of the major arterial road connecting the Central Coast to Sydney was closed. Source: Supplied / NSW Fire and Rescue
Cleaning the highway could take all day, drivers were warned.
Howard Collins, co-ordinator-general for Transport for NSW, told reporters on Friday: "You imagine [750kg] of finely ground steel, which is a very sharp metal object."
"It's not just a case of getting a road sweeper out or guys and girls with brooms.
"We are using some magnetic devices, removing embedded metal in the highway itself."
Transport for NSW's Howard Collins warned cleaning the highway could take all day. Source: AAP / Flavio Brancaleone
Dozens of tow trucks have been dispatched to more than 200 drivers, NRMA spokesperson Katrina Usman told the Australian Associated Press.
"Our patrols are able to fix (single punctures) on the side of the road," she said.
"But for cars with multiple wheels damaged, we've provided tows ... as of this morning, it was nearly two hours (to wait) for roadside assistance or a tow truck."
Trucking company apologises
The trucking company behind the metal spill apologised and pledged to foot the bill for impacted drivers.
Daniel Falconer of NJ Aston Group told 2GB radio: "We're very sorry for all the concern."
"Thank God that no-one's had a major accident or anything."
Drivers of B-double trucks were advised to park until the motorway reopened, while other drivers could use the old Pacific Highway.
