Hundreds of pounds have been stolen from a fruit machine at an amusement arcade at Skipsea Sands Holiday Park.
Police want to speak to three men who allegedly tampered with the machine with a metal rod so it could be played for free.
A spokesman said: "Over £800 in coins was eventually taken out of it.
"We have a CCTV image of the men. Can you help us identify them? Did you see them at the time?
"Two of the men were quite heavily built, and the third was skinny and wearing a baseball cap."
The incident happened between 7pm and 8.30pm on May 17. Call 101 quoting reference 16/56065/18.