Officers are investigating a suspected arson at a farm on Wroot Road in Epworth last night.
Humberside Police were called to the scene at around 9.10pm following reports around 1,000 hay bales were alight.
Humberside Fire and Rescue attended the scene to bring the fire under control and believe it had been started deliberately.
Turbary Road was closed from Idle Bank to Epworth.
Officers are keen to speak to three men seen in the area near a dark coloured Honda Type R.
Anyone with information is asked to call 101, quoting log number 553 of September 30. Alternatively, call Crimestoppers 0800 555111.