A speed camera was badly damaged after arsonists set fire to it twice.
The speed camera on the A1067 Fakenham Road in Taverham was set alight between 11.50pm on Monday September 10 and 12.05am on Tuesday 11.
Arsonists struck again between 12.30am and 12.50am on Tuesday September 18.
Officers want to speak to anyone who may have seen anything suspicious.
Contact PC Rachel Precious at Aylsham Police Station on 101 or Crimestoppers on 0800 555 111.
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