More on KentOnline
Police were stunned when they pulled a learner over for lane-hogging - to find both the pupil and instructor allegedly high on drugs.
In what is thought to be the first case of its kind, both men tested positive for cannabis after being stopped on the M2 near Strood.
Kent Police's roads unit made the discovery at 2.30am yesterday when the car was stopped on a junction of the M2 near Strood.
Officers tested the learner driver and found him with both cannabis and cocaine in his system.
But because he had a provisional licence, officers also tested the supervisor sat in the passenger seat and discovered he also gave a positive test.
He was also found in possession of cannabis.
A spokesman said: "Two men have been arrested on suspicion of driving whilst unfit through drugs.
"A 24-year-old from London and 27-year-old man have been bailed whilst enquiries continue until 18 July.
"The pair were arrested by the roads policing team at around 2.45am yesterday on the M2 (Rochester)."