VANDALS broke into a Bangholme property and torched a trailer filled with hay last Tuesday.
Police said the raiders ripped a gate off its hinges at a Harwood Road property about 3.10am on 21 January.
They entered the paddock, found a six by four cage trailer containing hay bales and set it alight.
The owner, a 53-year-old Frankston man, arrived at the scene a short time later to perform his regular farm duties, saw the fire and called triple zero.
The CFA attended and extinguished the flames but the trailer and hay bales were destroyed.
Call Crime Stoppers on 1800 333 000 with any information.
