Arsonists struck eight times overnight which included setting fires at a park, torching a derelict building and vehicles.
A patch of grassland went up in flames in Midhurst Road, Birley Carr in Sheffield at 7.30pm.
A crew from Rivelin Fire Station spent 30 minutes at the scene.
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An hour later crews were called over to Emerson Avenue in Stainforth, Doncaster, where a derelict building had been set on fire.
Thorne firefighters discovered a pile of litter on fire inside. They spent about an hour tackling the blaze.
Arsonists set fire to a skip in Wordsworth Avenue, Parson Cross, at 8.45pm.
Rivelin firefighters spent 20 minutes at the scene.
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A pile of litter was ignited in Munsbrough Lane, Munsbrough, at 9pm.
A fire crew dealt with the blaze within 15 minutes.
Yobs set fire to a motorbike in Campsall Balk, Norton in Doncaster at 9.05pm.
Adwick firefighters put the fire out within 30 minutes.
A pile of litter was set on fire in Gulthwaite Common Lane, Upper Whiston, at 9.45pm.
A crew from Aston Fire Station spent 15 minutes extinguishing the blaze.
A wheelie bin was set on fire in Endcliffe Park, Sheffield, at 9.50pm.
Firefighters from Sheffield Central Fire Station put the blaze out.
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A Ford Fiesta went up in flames in South Street, Rawmarsh, at 2.20am this morning.
A crew from Rotherham Central Fire Station extinguished the blaze.