2 appliances from Ryde, 1 appliance from Newport and 2 water carriers from Freshwater and Ventnor are tackling the blaze at Plaish Farm off Bowcombe Road.
Emergency services were called to the scene at 20:55.
Crews are wearing breathing apparatus and are using jets in an attempt to contain the fire, which has engulfed a large barn approximately 20x15m in size.
UPDATE @ 22:50 – The firefighting efforts continue tonight with crews taking a defensive stance as sections of the roof collapse.
No one has been injured, although 3 horses have been led to safety.
Fire crews are expected to remain on the scene throughout the night and into tomorrow morning.
Monitor jets are being put in place overnight and it is hoped that within the hour the incident can be scaled back.
The Environment Agency have been informed of the incident.
The cause of tonight’s blaze is currently unknown, however the Isle of Wight Fire and Rescue Service will be working with the farm owner to identify possible options.
UPDATE THURSDAY – Just 1 appliance remains on scene at Plaish Farm this morning after the incident was scaled back overnight.
The fire has been extinguished however firefighters are keeping a watchful eye on what remains of the smouldering hay.
An investigation into the cause is to get underway later today.
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