A fire at a derelict industrial building in Fernhurst is believed to have been started deliberately.
West Sussex Fire and Rescue was called to Midhurst Road at around 2:30 this morning.
At its height, six fire engines, a water carrier and an aerial ladder platform were at the scene.
Crews surrounded and extinguished the blaze, with one fire crew due to return later today.
A spokesperson for West Sussex Fire & Rescue Service said: "At 2.37am we responded to a fire at a derelict industrial building in Midhurst Road, Fernhurst.
"Upon arrival crews were confronted with a fire affecting the whole building.
"At the height of the incident, six fire engines, a water carrier and aerial ladder platform were at the scene. Sussex Police were also in attendance.
"Firefighters worked hard to surround the fire and extinguish it using hose reels, jets and thermal imaging cameras.
"The fire is believed to be of deliberate ignition.
"One fire crew will return to the scene later today to carry out another inspection of the area."
A Sussex Police spokesperson said: "Police responded to a report of an attempted burglary at a warehouse in Midhurst Road, Fernhurst, at 2am on Monday, 24 August.
"On arrival they discovered a fire within the property and alerted fire service colleagues.
"The fire, which caused significant damage, is being treated as arson.
"Officers are appealing for anyone who was in the area between 1am and 3am and who may have witnessed suspicious activity or anyone with information to contact police on 101, quoting 74 of 24/08."
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