Two passengers were initially spotted hanging out of the window of a car inside the M8 tunnel before a third emerged.
Exclusive: Drivers in Sydney's M8 motorway tunnel have captured the alarming moment three people emerged from a car to sit on the windows of the moving vehicle.
In a video that emerged last night, two passengers were initially spotted fist-pumping as they were hanging out of the window of a white sedan inside the tunnel that has a speed limit of 90km/h.
"It's incredibly dangerous, these are constrained roads, people are going at high speed. This is absolutely stupid," NSW Roads Minister John Graham said.
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A third person emerges from the vehicle shortly after, losing his hat as the trio car-surfed in one of Sydney's busiest motorways.
Drivers who were travelling behind the scene were left shocked.
"What the f---, that's literally the driver," one witness said as they filmed the act.
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"The car is swerving around."
The video has caught the eye of police, who are now hunting for the culprits responsible for the dangerous stunt.
As well as being filmed by witnesses, the act was captured on CCTV in the tunnel.
"If you're stupid enough to engage in this behaviour, you're probably stupid enough not to realise you're on CCTV," Graham said.
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