Devon and Cornwall Police are warning drivers to drive appropriately and stay safe after a cold night has left many roads icy.
Standing water is creating the high chance of ice forming, and drivers are being warned to be extra careful on Devon roads.
The cold weather has contributed to a string of incidents on the region's roads today, say police.
At 5:45am police were called to the A30 eastbound at Sourton Cross where a 3.5 tonne van had slid into the crash barrier.
Photo by Vincent Miller. Police car in head on collision on Prince Charles Road in Exeter
The crash closed the road and traffic was diverted through Okehampton.
This caused slow traffic on the A30 westbound at Meldon.
The driver did not suffer any injuries, police reported.
Another two vehicles left the road in Tavistock in two separate crashes.
One car overturned near Whitchurch turn off at 7:05am, along with another car which crashed in the same location.
Police say the two cars were a Citroen Xara and a Vauxhall Astra.
The fire service made one of the vehicles safe and a recover truck is removing the wreckage of the overturned car.
Police are also asking motorists to avoid Prince Charles road area in Exeter this morning.
A police spokeswoman said: "It appears the driver of a Silver Mitsubishi Carisma suffered a medical episode and crashed over a barrier hitting a police car."
The male driver of the Carimsa was temporarily unconscious and an ambulance was called.
The two police officers in the white Ford Focus police car were uninjured and are directing traffic.
The road will be blocked until both vehicles have been recovered.
James Dashwood, of the the Beacon Bus-Coach Company in North-Devon has taken to Facebook to warn motorists of ice on the A377 just past Bishops Tawton.
He posted a waring on thisisdevon's Facebook page which read: "I hit a big sheet of black ice this morning on the A377, heading towards Umberleigh.
"It's on the bend just before the low bridge. There is a flow of water crossing the road, looks like the splash off has frozen over night and will stay that way until the sun hits it. Please take care if passing there and in general on the dark side on the roads."
A small bridge near Kingsbridge is completely blocked this morning after a tractor and car collided.
The black Renault Megane and the tractor crashed on Bowcombe Bridge at 9:08am.
The Devon Air Ambulance was called to a crash at Crediton today.
A silver Toyota Yaris came to rest on its roof at Creedy Bridge near the Shoebrook turning.
The driver of the Yaris was walking wounded and the Air Ambulance was stood down.
Ice was reported in the area at the time.
On the A361 near Barnstaple a two-car crash left fluid leaking onto the road.
A BMW and a Peugeot collided just outside Barnstaple heading towards South Molton at 9:07am.
Occupants of both cars were out when police arrived.
Fire crews were stood down when the leaking fluid was found to be coming from the radiator and was not fuel.
Hazardous driving conditions have also been reported on the A361 in Ilfracombe at Mullacott Cross roundabout.
Today's freezing temperatures and slippery roads have promoted a warning from the police who are asking drivers to take extra care.
"Ice and very low, very bright winter sunshine all adding to the mix - take care," tweeted Topsham police officer Sarah Giles this morning.
The following is advice from Devon County council on winter driving:
Driving on snow and ice can be challenging and has safety and financial consequences for the unwary.
It is important to prepare your car properly, to clear all of the windows and also the lights of snow, not forgetting to clear the roof to prevent the snow sliding down the windscreen or blowing off distracting other road users. You must also clear your number plates.
When driving on icy and snowy roads the golden rule is to drive very slowly, ice can be patchy. When using the controls it is important to have a light and delicate touch, driving at the lowest speed and in the highest gear possible. Remember to allow more time for your journey.
It is important to have a safe separation distance from the vehicle in front, the usual of advice of the two second is not enough in icy conditions, braking distances can be as much as ten times as much. Even the car on the right is only about 65m from the car ahead, about 1/3 of the possible stopping distance.
• Be particularly careful when on hills and making turnings as the tyres may not have enough grip
• If you do become stuck in snow or on ice then try using a higher gear to move away, this may give you the traction you need
• If you are still stuck then placing an old blanket under the driving wheels, usually the front, may get you going again
• Keep the lights, windows and mirrors clean and free from ice and snow
• Keep your battery fully charged
• Add anti-freeze to the radiator and winter additive to the windscreen washer bottles
• Make sure wipers and lights are in good working order
• Check that tyres have plenty of tread depth and are maintained at the correct pressure.
• Visibility can be seriously reduced and the use of dipped headlights is essential in falling snow
• Watch out for fog - it drifts rapidly and is often patchy
• In foggy conditions, drive very slowly using dipped headlights
• Use fog-lights if visibility is seriously reduced, but remember to switch them off when visibility improves
• Don't hang on to the tail-lights of the vehicle in front. This gives you a false sense of security and means you may be driving too close
• Don't speed up suddenly, even if it seems to be clearing. You can suddenly find yourself back in thick fog
• In fog, you think you are travelling slower than you really are