Average speed cameras along the A90 have cut the number of speeding drivers, according to a survey.

Cameras installed along the 51.5 mile route between Dundee and Stonehaven started working on October 31 last year in an effort to improve road safety.

Speed surveys carried out by Transport Scotland in December found that one in every 100 vehicles broke the speed limit, while three in every five cars were speeding prior to the installation of the cameras.

The survey also found that only one in every 5,000 vehicles are now speeding at more than 10mph over the limit, when previously it was one out of every five vehicles.

Transport Minister Humza Yousaf said: "These findings add to the compelling evidence that average speed cameras help to transform driver behaviour.

"I'm confident that this encouraging improvement in speed limit compliance along the length of the A90 will help to reduce casualties in the same way as has been achieved with similar average speed cameras on the A77 and A9."

He added: "While the previous strategy of fixed cameras and mobile enforcement saw casualties reduce at a number of camera locations across the route, the £2m investment in average speed cameras on the A90 have had a significant positive impact over the 51.5 mile stretch of the A90 in a very short period.

"The Scottish Government is committed, through Scotland's Road Safety Framework to 2020, to achieving safer road travel, reducing the number of serious injuries and working towards an ultimate vision of zero fatalities on our roads.

"This is another step towards achieving our ambitious vision."

Area Commander for Road Policing North, Chief Inspector Stewart Mackie, said: "I am delighted that the initial results from this project has had such a dramatic effect on driver behaviour, which is what they were intended to do.

"Reducing excessive speed on this road directly corresponds with reducing the chances of people being injured and killed in road traffic collisions."