Police are now being trained in the use of new 3D laser scanning cameras that will significantly reduce the time Scotland's trunk roads are closed following serious accidents.

Police Scotland and Transport Scotland say the five new 3D scanners, each costing £50,000, are accurate to within millimetres and are capable of capturing an entire collision site more accurately and quickly than traditional methods.

The scanners record up to a million points per second while rotating 360 degrees, recreating a virtual image enabling officers to view the scene from any angle.

The data is then transferred to a laptop to be worked on remotely, where officers can use the 3D image to oversee the crash site, the proximity of vehicles involved and other relevant aspects of the scene.

Twenty officers are being trained initially.

Inspector Darren Faulds, Police Scotland Driver Training, said: "At the moment, if there is a serious or fatal crash, the road is closed to allow those who have been injured to receive treatment and to protect those working at the scene.

"During this time, officers will examine the scene before recording each point of evidence manually using traditional surveying equipment.

"The virtual survey taken by the new scanners can be done in less time and this, combined with prudent scene management, will make a significant impact on the time taken for investigations at crash sites."

Trials in England in 2009 showed the laser scanners could reduce incident clear-up times by an average of 39 minutes. But the time saving can be far greater.