A £10,000 motorway speed camera has been cut down with a blow torch and thrown off a bridge in Devon.
A spate of attacks in Plymouth saw three cameras damaged
The Devon and Cornwall Police camera was monitoring the 50mph speed limit imposed at roadworks on the southbound lanes of the M5 near Exeter.
Officers spotted the camera in a river below the bridge.
Devon and Cornwall Police spokesman Pc Roy Adams said: "We are assuming it was a disgruntled motorist who was caught speeding on Wednesday night."
Their purpose is to change driver behaviour
Devon and Cornwall Police
Pc Adams said the camera was a write-off and the film inside would have been ruined.
He said: "So if anyone was driving there on Wednesday night and they were flashed at
by the camera, the evidence is now at the bottom of the river."
It is not the first time speed cameras have been attacked in the county.
In 2001, three cameras were attacked in Plymouth when tyres were put over them and set alight.
However, the Plymouth attacks and the Exeter incident are believed to be unrelated.
Devon and Cornwall Police said of their cameras: "The most common myth is that cameras are there to catch motorists out and raise revenue, but their purpose is to change driver behaviour.
"Evidence shows that safety cameras play a significant role in preventing accidents. On average the number of drivers speeding at camera sites drops from 55% to 16%."