Equipment worth £50,000 has been stolen from a building site in Downham Market.
The theft took place at Bexwell Road between 6pm on Monday and 6.45am on Tuesday.
Norfolk Police said the building was broken into after the front fence was smashed open.
A fuel bowser/tank containing 2,000 litres of diesel, a large amount of heavy-duty hand tools and two air conditioning units were stolen.
Anyone with information is asked to contact PC Alexander Edwards at Norfolk Constabulary on 101 quoting reference 36/34544/22.