The incident allegedly happened on Friday evening after the planned Manx Grand Prix qualifying session was called-off due to rain on the course.
The Roads Open car drives along the famous Mountain Course after every Isle of Man TT and Manx Grand Prix race or session to signal that the roads on the course are open to the public and safe to drive on.
Tonight’s alleged incident happened in the area of Glentramman
Officers from the Isle of Man Constabulary are currently at the scene as part of their investigation into the alleged incident.
A ‘local driver’ is currently assisting officers with its enquiries, according to the force.
Following the alleged incident, the police sent out a strongly worded message online reminding drivers of the rules of the road on the island regarding the Roads Open Car.
It said: ‘It is imperative that drivers, riders and pedestrians alike do not assume the road is open and must ensure that the Roads Open car has passed their location, if it has not, the road remains closed and entering it is an offence.
‘Take an extra 30seconds to observe for “normal” traffic flow, check social media feeds, listen to local radio transmissions or check with marshals nearby.
‘It could literally be the difference between a trip to the shops or a trip to custody.’